The presence of a child with an intellectual disability is often perceived as a cloud hanging over the heads of their siblings, placing them at risk of developing a variety of problems. Only recently have siblings been examined for the positive aspects of this life situation, such as the potential to experience psychological growth. Adopting J. A. Schaffer and G. H. Moos' (1992) theoretical framework, this study investigated the contribution of perceived stress, self-differentiation, and parental preference to the personal, social, and spiritual growth of siblings. Participants comprised 101 siblings of children with intellectual disabilities and 89 siblings of children with typical development (age range = 13–19 years). Results indicated that siblings of children with intellectual disabilities evidence higher levels of growth, with self-differentiation and perceived maternal preference acting as the main contributors to this growth.
Relationships with siblings constitute one of the most enduring and significant social bonds. In addition to siblings who enjoy companionship, help, affection, role modeling, and social comparison, there are those who experience jealousy, competition, and even hate. Whatever form these relationships take, however, they impact strongly the individuals' adult lives, affecting emotional, cognitive, social, and professional development (Coles, 2003; Vandell & Bailey, 1992).
The lives of children may change dramatically when their brother or sister is diagnosed with an intellectual disability (McHale & Gamble, 1989). Everyday life for these siblings is inevitably a challenge and may involve dependence and lifelong caregiving responsibilities. Adolescence can be a particularly demanding time, as siblings respond to the strong pressure of their peers, which is typically a hallmark of this age. The struggle of the adolescent to define him/herself as an individual is generally bound up with attempts to loosen familial ties in terms of both emotional attachments and parental authority. Consequently, siblings of children with disabilities may often be torn between the developmental task of separation individuation and feelings of guilt and commitment to their brother or sister (Marshak, Seligman, & Prezant, 1999).
Adopting the psychopathology model, some studies have characterized the siblings of children with disabilities as being at risk for a variety of psychological and somatic complaints, behavior problems, and social isolation (e.g., Bagenholm & Gillberg, 1991; Gamble & Woulbroun, 1993; Mandleco, Olsen, Dyches, & Marshall, 2003). Recently, however, researchers have argued that these siblings are no more likely to experience problems than are siblings of children with typical development. In their meta-analysis, Rossiter and Sharpe (2001) found that having a brother or sister with an intellectual disability had only a small negative effect on the functioning of their siblings, which was insignificant for adolescents, suggesting that “the generalized concern about the social and psychological development of these siblings is overstated” (p. 76). In a comprehensive overview of research themes regarding siblings of children with disabilities in articles published between 1990 and 2004, Stoneman (2005) showed that in terms of sibling relationship quality, behavior problems, emotional reactions, and internal resources, siblings of children with disabilities did not differ from siblings of children with typical development, and there was some evidence that sibling relationships involving a child with a disability may even be more positive. Furthermore, in the last decade, examinations of families of children with intellectual disabilities conducted from the perspective of positive psychology indicated that although their experience is not necessarily easy, it may lead to a fuller and richer life (Knox, Parmenter, Atkinson, & Yazbeck, 2000). More specifically, parents of children with developmental disabilities have indicated the positive impact of the child, expressed in a changed perspective on life, increased sensitivity, the opportunity to learn, improved family dynamics, stronger religious faith, and more (Taunt & Hastings, 2002). These findings are in line with the developing theory of positive psychology. Breaking the tradition of the focus on what is wrong with people, positive psychology asks what contributes to people doing well, to being happy, and thriving, beyond the amelioration of psychological suffering (Dykens, 2006). Furthermore, positive psychology advocates a shift from deficits to strengths, abilities, happiness, and flow (Seligman & Csikszentmihalyi, 2000). According to Folkman and Moskowitz (2000), although positive affect has not been entirely neglected, most models of stress do not emphasize positive affect and growth. Growth refers to positive psychological changes experienced as a result of the struggle with demanding life circumstances (Tedeschi & Calhoun, 1995), which require adaptive resources and challenge the way people understand the world and their place in it (Janoff-Bulman, 1992). The field of intellectual disabilities can gain more from the use of this perspective to assess the full range of effects that are associated with having a family member with an intellectual disability. Although recent research has considered the positive impact of a child with an intellectual disability on the parents (Hastings & Taunt, 2002; Hastings, Beck, & Hill, 2005; Taunt & Hastings, 2002), the impact on siblings has received little attention (Dykens, 2005;Stoneman, 2001).
Adopting the conceptual model of the positive outcomes of stress proposed by Schaefer and Moos (1992), the current study focused on the experience of being a brother or sister of a child with an intellectual disability. According to Schaefer and Moos, four factors contribute to growth: (a) personal characteristics, including individuals' sociodemographic characteristics and personal resources, which are operationalized in the present study as sociodemographic variables such as gender, age, number of siblings, and more; (b) characteristics of the environment, represented here by sibling's perception of parents' treatment and preferences; (c) characteristics of the life event, such as severity, duration, and scope, examined here in terms of the level of stress as reported by the sibling; and (d) coping responses, operationalized in our research as differentiation of the self.
Various sociodemographic factors are expected to affect growth. Previous studies indicate that family characteristics, as well as characteristics of both siblings may be important contributors to siblings' adjustment. Hence, siblings appear to fare better when the family is larger (Gallagher & Powel, 1989; Rodger, 1985), the socioeconomic circumstances are good (Breslau & Parbucki, 1987), the siblings are younger than the child with the disability (Atkins, 1989; Hodapp & Urbano, 2007), and the disability is less severe (Pit-Ten Cate & Loots, 2000).
The environmental characteristic of perception of parents' treatment is, by definition, not the same for all the children in the family (Plomin, Asbury, & Dunn, 2001). Children are treated in different ways by their parents and experience their parents' behavior differently. Moreover, young children's and adolescents' experiences of differential supportive and disciplinary parenting have been linked to a variety of indicators of social and emotional adjustment, including sense of competence, self-worth (Dunn, Stocker, & Plomin, 1990), behavioral problems, and psychopathology (Tejerina-Allen, Wagner, & Cohen, 1994). Because of the extended physical and emotional needs of children with disabilities, perceived parents' treatment is a crucial issue among siblings in these families. In a study of siblings of children with cystic fibrosis, Quittner and Opipari (1994) concluded that they were at risk for experiencing the negative effects of differential treatment, as their mothers not only spent more time with the child with the illness but also rated this time as more positive than time spent with the healthy sibling. On the other hand, according to Stoneman (1998), differential treatment may have distinctive meaning in families of children with disabilities and may be interpreted not as parental favoritism but as a justified response to the greater caretaking needs of the child with the disability. Despite such indications of the importance of differential parenting in shaping a child's development, relatively little theoretical and empirical research has focused on this issue, and to the best of our knowledge, even less has specifically considered brothers and sisters of children with intellectual disabilities. In the present study, we addressed this gap by examining the contribution of perceived differential parenting to the sibling's personal growth.
Characteristics of the life event were examined here by the sibling's level of perceived stress. As defined by Gamble and Woulbroun (1993), perceived stress consists both of stressors in family relationships, such as problems associated with meeting affectional needs and developing an identity, and stressors in relationships with peers and the community, including informing friends, protecting the child with a disability from discrimination, feelings of shame, and isolation of the family. However, relationships between siblings in all families may be stressful and challenging. Shame, guilt, competition, and envy are part of siblings' relationships by nature. These relationships might result in costs and benefits in terms of negative and positive impacts (e.g., Coles, 2003; Vandell & Bailey, 1992). Thus, in our view, the higher a child's perceived stress is, the less personal growth he or she will experience.
The factor of coping responses in Schaffer and Moos' model is operationalized in the current study as self-differentiation, which is indicative of emotional and social maturity. Differentiation of the self, as conceptualized by Bowen (1990), refers to the ability to distinguish and integrate the emotional and intellectual aspects of the personality; it contains both intra- and interpersonal dimensions. In persons with high self-differentiation, emotions and thoughts work in tandem; in the case of low self-differentiation, emotions overpower thoughts or thought displaces emotion. People with high self-differentiation are able to feel and express their emotions, to contain their impulses, and to respond to stress and crises with flexibility, self-control, and responsibility. In addition, according to Bowen, the level of self-differentiation also affects the degree of differentiation from others. Persons with low self-differentiation tend to fuse with others more, show greater dependency, or, alternatively, be more inclined to withdraw and cut themselves off from others. In contrast, those with high self-differentiation show greater ability to separate the self from others. During adolescence there are often strongly conflicted feelings about freedom from and dependency on one's family, and peers are typically those who are instrumental in helping adolescents cope with individuation and separation. However, the experience of growing up with a brother or sister with an intellectual disability may be accompanied by embarrassing personal and social circumstances that arouse feelings of shame, guilt, or isolation (McHale & Gamble, 1989). Although the sense of social rejection is difficult to bear at any stage in life, it is most crucial in adolescence, when acceptance by one's peers is of prime importance (Faircloth & Hamm, 2005). Therefore, the level of self-differentiation and ability to separate from their brother or sister might be expected to affect siblings' poten tial to grow and benefit despite their unique situation.
In the current study, we examined the relative impact of all these factors on siblings of children with intellectual disabilities, and the extent to which they contribute to their psychological growth. To this end, we first examined the differences between siblings of children with and without intellectual disabilities in terms of level of stress, differentiation of self, perception of parental treatment, and growth. Then, we examined the associations among all the research variables and, last, the unique and combined contribution of the independent variables to the three aspects of growth of the siblings in both groups. In view of the existing literature, we predicted that the presence of a child with an intellectual disability in the family, higher self-differentiation, and lower level of stress would be associated with higher levels of growth, whereas a higher perception of differential parenting would be associated with lower levels of growth among siblings.
A total of 190 teenagers, ranging in age from 13 to 18 years (research group M = 15.49, SD = 1.80; comparison group M = 15.40, SD = 1.63) and living in intact families in the center of Israel, participated in the study. Of these, 101 were siblings of children with mild and moderate intellectual disabilities who lived at home, and 89 had brothers or sisters with no disability. The participants in the comparison group were matched with those in the research group in terms of primary demographic characteristics (i.e., age, sibling's age, and neighborhood). The demographic characteristics of the sample are shown in Table 1 .
As can be seen from Table 1, groups did not differ in terms of gender, birth order, or health status. However, families of children with intellectual disabilities had more children, were more religious, and reported lower economic status.
The Stress Related Growth Scale (Park, Cohen, & Murch, 1996) was used to assess the positive outcomes of a stressful event relating to personal, social, and spiritual outcomes. The original scale contains 50 items, 26 of which we selected and adapted to Israeli adolescents. In the current research, a factor analysis revealed three factors that explained 47% of the variance: Personal Growth (14 items; e.g., “I learned to cope better with uncertainty,” “I learned to take more responsibility for what I do”), Social Growth (9 items; e.g., “I learned to respect other's feelings and beliefs,” “ I became more accepting of others”), and Spiritual Growth (3 items; e.g., “My trust in God increased,” “I developed/increased my faith in God”). Participants were asked to indicate the degree to which they agreed with each statement in the questionnaire on a 3-point scale, from 1 (not at all) to 3 (very much). Cronbach alphas for the factors in the current study were .87 for Personal Growth, .84 for Social Growth, and .86 for Spiritual Growth. Each participant was assigned a score for each of the three subscales by averaging his or her scores on the relevant items.
Participants completed a demographic questionnaire relating to age, gender, birth order, number of siblings, health status, family's economic status, and degree of religiosity.
The Perceived Family Relationship Questionnaire is part of the self-report Family Relations Test (Bene & Anthony, 1957), which was translated into Hebrew and adapted by Frankel (1968). The current study used 20 items examining the perceived level of father's and mother's preference (10 items each), phrased so 5 five items indicated a positive attitude to the brother or sister (e.g., “My mother never complains about my brother/sister in comparison to other children in the family,” “Of all the children in the family, my father loves my brother/sister the most,” “My mother devotes most of her time to my brother/sister”) and 5 indicated a negative attitude (e.g., “Of all children in the family, my mother is always willing to punish my brother/sister,” “Of all children in the family my mother always says that my brother/sister is causing most of the problems in the family”). Participants were asked to refer to the child with the disability in the research group and to the child at the same age in the comparison group and to rank the degree to which they agree with the statements on a Likert scale from 1 (strongly disagree) to 4 (strongly agree). The instrument yielded an internal consistency of Cronbach alpha .86 for mother's preference and .85 for father's preference.
The Perceived Stress Related to the Brother or Sister factor was measured by 13 items taken from the Diabetes Quality of Life Scale for young people (Ingersoll & Marrero, 1991) and adapted for purposes of the present study. The items were chosen for their relevance to the stress experienced by siblings in general and being a sibling of a child with a disability in particular (e.g., “To what extent do you feel embarrassed when you are with your brother or sister in public?”, “To what extent does your brother or sister limit your social relationships?”, “To what extent does your brother or sister interfere in family life”?). Participants were asked to indicate the degree to which they agreed with each of the 13 statements on a 5-point Likert scale, from 1 (not at all) to 5 (very much). Because the Cronbach alpha for the entire questionnaire in the current study was .74, a perceived stress score was calculated for each participant by averaging his or her scores on all 13 items, with higher scores reflecting greater stress.
The Level of Differentiation of Self Scale (LDSS; Haber, 1984), which is based on Bowen's conceptualization of this characteristic, consists of 32 statements tapping two major variables: emotional maturity (e.g., “ I can solve problems if I'm emotionally upset”) and emotional dependency (e.g., “My actions and decisions are based on the agreement of other people”). Respondents are asked to indicate the degree to which they agree with each statement on a 4-point Likert type scale ranging from 1 (strongly disagree) to 4 (strongly agree). The LDSS was translated into Hebrew, revalidated, and adapted by Baum and Shnit (2005), who reported a high reliability of (Cronbach α = .91) for the final version. Reliability in our current study was .84. Therefore, a self-differentiation score was calculated for each participant by averaging his or her scores on all 32 items, with higher scores reflecting higher levels of self-differentiation.
Social workers in local welfare services approached, first via telephone, the parents of children with intellectual disabilities with whom they were in continuous professional contact. They asked their permission to include their children in the current research, assuring their anonymity. Only when their consent was given did the research assistants visit the families at their homes and administer the instruments to the siblings privately, assisting them in completing the questionnaires where necessary. The entire procedure took approximately 30 min. At the end of the visit, each participant was asked to provide a name of a friend or classmate who had a brother or sister of a similar age as their own, but with no disability. The parents of these children were contacted by telephone by the same research assistants to obtain their informed consent, and the children were interviewed using the same procedure as with the research group. These siblings were requested to relate in their answers to their brother or sister who was at the same age as the child with the disability in the matched family. Participation rate was 84.2% for the research group and 80.9% for the comparison group.
The first stage of data analysis compared siblings of children with and without intellectual disabilities in respect to personal, social, and spiritual growth and their predictors, namely, perceived stress, self-differentiation, and mothers' and fathers' preferences. Two 1-way multivariate analyses of variance (MANOVAs; one for the three aspects of growth and the other for the independent variables) yielded significant differences between the groups in regard to the aspects of growth, F(3, 185) = 16.06, p < .001, η2 = .21, and the predictors, F(4, 184) = 7.21, p < .001, η2 = .14. The means and standard deviations appear in Table 2 .
As can be seen from Table 2, univariate analyses of variance (ANOVAs) for each measure revealed significant differences between the groups, indicating higher levels of personal, social, and spiritual growth among siblings of children with intellectual disabilities. In addition, significant differences were found between the groups in regard to perceived mothers' and fathers' preferences, F(2, 186) = 12.51, p < .001, η2 = .12, respectively, with siblings of children with intellectual disabilities reporting higher levels of perceived preference for the brother or sister on the part of both parents. No differences were found between the two groups for level of stress or self-differentiation.
To examine whether there were differences between the groups on perceived mothers' versus fathers' preferences, a 2 × 2 MANOVA was conducted (Group × Mother/Father), with repeated measures for each parent. No significant difference emerged between the two parents, F(1, 187) = 3.65, p > .05, and no significant interaction was found for Group × Perceived Mother's/Father's Preference, F(1, 187) = 0.92, p > .05.
In the second stage of data analysis, Pearson correlations were performed between all dependent and independent variables for each group. The results of these correlations are presented in Table 3 (the upper half of the table represents the research group and the lower half represents the comparison group).
As Table 3 reveals, personal growth was positively and significantly associated with self-differentiation in both groups and with mother's preference only in the research group. Social growth was negatively and significantly associated with perceived stress and positively associated with mother's preference in the research group, and spiritual growth was associated negatively with perceived stress in the research group and positively with mother's preference in the comparison group. In other words, among siblings of children with intellectual disabilities, a lower level of perceived stress was related to higher social and spiritual growth, higher self-differentiation was related to higher personal growth, and higher perceived mother's preference was related to higher social growth. Among siblings of children without a disability, higher self-differentiation was related to higher personal and spiritual growth. In addition, stress was negatively associated with self differentiation and positively with mother's preference in the comparison group, and mother's preference was highly positively associated with father's preference in both groups. To examine the contribution of the sociodemographic variables to differences in experienced growth between the groups, two-way MANOVAs (Group × Sociodemographic Variable) were conducted. Results showed no significant differences regarding gender or number of children in the family. However, birth order yielded significant differences, F(3, 171) = 3.33, p < .01, η2 = .03, with older siblings showing higher personal growth (M = 72.58, SD = 15.67) and social growth (M = 67.31, SD = 16.46) than younger siblings (M = 74.49, SD = 15.46; M = 68.60, SD = 18.04, respectively). No significant interaction of Group × Birth Order was found, F(3, 171) = 2.31, p > .05.
To examine whether differences existed in respect to the dependent and independent variables among the three religious categories (secular, traditional, orthodox) and whether differences between the research groups could be explained by the differences in religiosity, a 2 × 3 MANOVA (Groups × Three Religious Categories) was conducted. In regard to the independent variables, no significant differences were found for religiosity, F(8, 362) = 2.11, p > .05, and no significant interaction was found for Groups × Religiosity, F(8, 362) = 1.48, p > .05. However, in respect to the association between religiosity and growth, the two-way MANOVA revealed significant differences among the three categories, F(6, 362) = 11.36, p < .001, η2 = .16, as well as a significant interaction for Group × Religiosity, F(6, 362) = 2.34, p < .05, η2 = .04. Separate ANOVAs for personal, social, and spiritual growth showed that growth was lowest among secular siblings (M = 65.61, SD = 14.62; M = 67.64, SD = 17.40; and M = 47.12, SD = 20.30, respectively) compared with the traditional siblings (M = 72.83, SD = 17.91; M = 73.53,SD = 18.91; and M = 71.65, SD = 24.11, respectively) and the orthodox siblings (M = 71.99, SD = 13.94;M = 74.12, SD = 15.24; and M = 81.20, SD = 22.60, respectively). A paired-comparison Scheffé test revealed a significant difference on spiritual growth between secular siblings and the other two groups. In addition, separate ANOVAs for each aspect of growth showed significant interactions for all three measures, F(2, 183) = 3.75, p < . 05, η2 = .04; F(2, 183) = 3.11, p < . 05, η2 = .03; and F(2, 183) = 3.16, p < . 05, η2 = .03, for personal, social, and spiritual growth, respectively. Thus, siblings of children with intellectual disabilities showed higher levels of growth than the comparison group; however, even though the differences in personal and social growth were salient only among secular and traditional siblings, the difference in spiritual growth between the groups was salient only among the traditional and orthodox groups.
Last, the associations among age, economic status, health, and growth were examined. Among siblings of children with intellectual disabilities, positive significant correlations were found between spiritual growth and age (r = −.30, p < .01), on the one hand, and economic status (r = −.26, p < .01), on the other, with siblings who were older and reported better economic status showing lower spiritual growth. In the comparison group, positive significant correlations were found between health status and growth (personal growth r = .31, p < .01; social r = .24, p < .05; and spiritual growth r = .18, p < .05) as well as a negative correlation between age and spiritual growth (r = −.22, p < .05). In other words, healthier siblings reported higher growth on all three aspects, and the older the siblings were, the lower their spiritual growth was. Fischer's Z tests revealed significant differences between the two groups in regard to the correlations between health status and both personal growth (Z = 1.97, p < .05) and social growth (Z = 1.96, p < .05), indicating that only among siblings of children without disabilities did those who reported better health status also experience more personal and social growth.
In the third stage of data analysis, three separate hierarchical regression analyses were carried out to examine the unique and combined contribution of the independent variables to the explained variance of the different aspects of growth. In all three analyses, demographics (age, birth order, religiosity, gender, health status, number of children in the family, and economic status) were entered in the first step. The group variable (siblings of children with intellectual disabilities vs. siblings of children without disabilities) was entered in the second step. The level of perceived stress and self-differentiation were entered for the third step, and perceptions of parents' preferences in the fourth step. The forced method was used to select the variables in each of these steps. In the fifth step, interactions among all the variables were entered. Because none of the interactions reached a significance level of .05, only the results of the first 4 steps are presented in Table 4 .
As can be seen from Table 4, siblings' spiritual growth accounted for the highest explained variance (46%), followed by personal growth (26%) and social growth (26%). Group accounted for a significant proportion of the variance, contributing 12% to social growth and 6% to spiritual and personal growth, with siblings of children with intellectual disabilities experiencing more growth of all kinds. In addition, birth order contributed significantly to personal and social growth, and economic status was negatively associated only with spiritual growth, indicating greater spiritual growth among siblings from families of lower economic status. Better health status contributed significantly to personal growth and younger age to spiritual growth. Number of children contributed to spiritual growth, indicating that in larger families, siblings reported higher spiritual growth. Not surprisingly, level of religiosity yielded a major contribution to spiritual growth (β = .42). Last, the coping resource of self-differentiation contributed significantly to sibling's personal growth, whereas the resource of perceived mother's preference contributed to social growth.
In the present study, we compared teenagers growing up with a brother or sister with an intellectual disability with siblings of typical development, seeking to identify possible predictors of their psychological growth as conceptualized by Schaffer and Moos (1992). The results revealed that considerably greater growth was reported by the adolescent siblings of a child with an intellectual disability. These adolescents indicated that they had discovered strengths and resources that were not necessarily evidenced by others their age, took on more responsibility, developed significant relationships, were more sensitive to others, and were able to get the most out of their lives and experiences. These results are in line with previous findings showing that many families of children with disabilities not only succeed in adjusting but report benefits and growth (Bennet, De Luca, & Allen, 1996; Hodapp, 1995). On the other hand, our findings pointed to a similarity in respect to the level of self-differentiation and perceived stress in the family between the two groups, along with a difference in perceived parental preference. Siblings of children with intellectual disabilities perceived that their mothers and fathers preferred their brother or sister and protected them more. Interestingly enough, whereas perceived preference of the brother or sister in the comparison group was associated with higher levels of stress, preference for the child with an intellectual disability in the family was associated with higher levels of personal and social growth. Findings of previous studies found a positive relationship between differences in parental treatment and poor psychological functioning (Quittner & Opipari, 1994). It would seem, therefore, that what is important is not necessarily the objective preference, but the manner in which it is interpreted (McHale & Harris, 1992). In line with Stoneman (1998), our findings also showed that, unlike the siblings of children with typical development, the siblings of a child with an intellectual disability tended to show an understanding that the reality in the family demanded favored treatment of their brother or sister and, consequently, did not feel deprived. On the contrary, they responded by displaying greater maturity and independence, expressed in personal and social growth. On the other hand, siblings of a child without an intellectual disability who felt that their mothers preferred their brother or sister and could not find an adequate explanation for this preference showed higher levels of stress and spiritual growth, thereby escaping to ex-familial sources.
We also found the level of self-differentiation, similar in both groups, to be associated with personal growth among siblings. Apparently, self-differentiation is crucial for teenagers, in general, and for children growing up in unique circumstances, in particular. As soon as the children were able to differentiate themselves from their brother and sister—that is, as soon as they did not suffer from feelings of guilt or the sense that they themselves were tainted by the disability—they were able to grow. This explanation appears to gain additional support from the finding that siblings of children with intellectual disabilities who experienced higher levels of stress in the family also showed lower social and spiritual growth.
Examination of the unique and combined contribution of the independent variables revealed that being the sibling of a child with an intellectual disability is, in and of itself, a challenge that leads to growth. The structural variables that have traditionally been examined, such as birth order, religiosity, economic and health status, and number of children, also played a role in both groups. Better economic status as well as greater religious belief, lower age, and larger family size were associated here with more spiritual growth. This is consistent with previous studies showing that children who report good socioeconomic circumstances also display better adjustment (Breslau & Parabucki, 1987). However, although previous findings have indicated that siblings who are younger than the child with the disability show better adjustment (Atkins, 1989; Hodapp & Urbano, 2007), we found older siblings to report higher personal and social growth. This may be a reflection of the difference between adjustment and growth. The turmoil resulting from stress appears to be an essential condition of growth. The birth of a child with an intellectual disability often triggers a crisis for the entire family, including older siblings, which may ultimately lead to a search for meaning and the development of internal resources, or in other words, growth. On the other hand, children who are born into a family with a child with an intellectual disability do not experience the same sort of upheaval, as they come into an existing situation to which they are likely to adjust as a matter of course.
As noted above, self-differentiation was found here to enable personal growth, whereas mother's preference for the other child contributed to social growth. This suggests that teenagers who are able to differentiate themselves from others and be independent are more capable of coping with challenges and hardships, a sign of personal growth. On the other hand, those who feel deprived of their parents' attention may reach out for external resources and peers' support, thereby experiencing social growth. Being the sibling of a child with an intellectual disability, therefore, appears to be an experience that encourages growth in a variety of forms. Despite their experience of parental preference, these children may display an understanding of their unique situation and, consequently, elicit the maximum potential from themselves, evidencing various aspects of growth.
Several possible methodological limitations of this study should be considered. First, we relied solely on siblings' self-reports. Future studies should seek to include additional measures, such as observations and data obtained from other relevant sources (e.g., parents, teachers, or other professionals) to obtain a more comprehensive picture of siblings' adaptation. Second, because the findings might be “time-bounded,” that is, age dependent, generalizability is limited to teenagers 13–18 years old. Future studies could examine younger and older siblings to determine the dynamics of their growth along the life course. Third, although in many ways Israel is representative of a Western society, culture-specific factors may have impacted the findings. It would be interesting to attempt to replicate the results in additional cultures to obtain cross-cultural validation.
These possible limitations notwithstanding, the present study may have critical implications for practitioners. The findings regarding psychological growth among siblings of children with intellectual disabilities should be translated into positive-psychology intervention programs aimed at meeting the unique needs of these young people and the brothers and sisters of children with other disabilities. Professionals could empower siblings by focusing on internal resources, which appear to lead to gains in terms of personal, social, and spiritual growth, despite the stress and burdens generated by this life situation.
We would like to thank Keren Shalem at the Central Fund for the Development of Services for Persons With Intellectual Disabilities in Israel for supporting this research.
Authors: Liora Findler, PhD (findler@ mail. biu. ac. il), Head of the Rehabilitation Track, The Louis and Gabi Weisfeld School of Social Work, Bar-Ilan University, Ramat-Gan, 52900, Israel. Aya Vardi, MSW, Social Worker, Asaf Harofe Medical Center, Israel