Broader Autism Phenotype and Perceived Social Support As They Relate to Pro-Social Behavior in Typically Developing Siblings of Children with Autism Spectrum Disorder

Background:  In light of difficulties associated with core symptoms of autism spectrum disorder (ASD), as well as the behavioral issues that often accompany ASD, having a child with ASD as a family member may be challenging. Research on parents of children with ASD has found negative outcomes, such as stress, depression, and anxiety (e.g., Karst & Van Hecke, 2012). With respect to outcomes for typically-developing (TD) siblings of children with ASD, the results are mixed (e.g., Meaden et al., 2010). Some research has found increased mood and behavior problems in TD siblings (e.g., Bitsika et al., 2015), whereas others have found no evidence for elevated emotional and behavioral difficulties (e.g. Tomeny et al., 2012), and still others have found positive outcomes (e.g., Macks & Reeve, 2007). Given the mixed findings for TD siblings of children with ASD, research should explore factors related to positive outcomes, such pro-social behavior, in these siblings.

Objectives: The present study sought to 1) explore pro-social behavior in TD siblings of children with ASD, and 2) examine broader autism phenotype (BAP) and TD siblings’ social support as they relate to TD siblings’ pro-social behavior, while controlling for family stressors (parental stress and ASD symptom severity of the child with ASD).

Methods:  Participants included 113 parents and TD sibling [ages 11 to 17 (M = 13.32, SD = 1.81)] of a child with ASD [ages 3 to 17 (M = 11.98, SD = 3.29). Parents completed the Questionnaire on Resources for Stress – Short Form as a measure of parental stress, the Children’s Social Behavior Questionnaire about their child with ASD to assess ASD symptom severity and about their TD child to assess BAP symptoms, and the Strengths and Difficulties Questionnaire (SDQ) to assess TD sibling pro-social behavior. TD siblings completed the SDQ and the Child and Adolescent Social Support Scale to measure their pro-social behavior and perceived social support, respectively.

Results:  A series of partial correlations were conducted controlling for ASD symptom severity and parental stress. While holding these covariates constant, pro-social behavior was negatively correlated with BAP symptoms (r = -.27, p = .004 for self- and r = -.57, p < .001 for parent-report), per both reporters. Alternatively, pro-social behavior was positively correlated with TD sibling social support for both reporters (r = .38, p < .001 for self- and r = .21, p = .03 for parent-report). Additionally, parent- and self-reported pro-social behavior were correlated, r = .43, p < .001.

Conclusions:  Overall, TD siblings reported pro-social behavior within the Normal range based on normative data (Goodman, 1997), indicating the majority of TD siblings in the present sample are exhibiting some positive behavioral outcomes, despite the potentially challenging factors associated with having a sibling with ASD. Greater pro-social behavior was related to fewer BAP symptoms and greater perceived social support, as reported by both parents and the TD siblings. Although these results are preliminary in nature, they emphasize that future research should examine predictive factors of positive outcomes for TD siblings of children with ASD.