Are typically-developing siblings of children with an autism spectrum disorder at risk for behavioral, emotional, and social maladjustment?

Existing literature regarding the adjustment of siblings of children with an autism spectrum disorder (ASD) remains inconclusive, with some studies showing positive adjustment, others showing negative adjustment, and others showing no difference when compared to siblings of typically-developing children. For the current study, 42 parents of a child with an ASD and a typically-developing sibling (ASD group) and 42 parents of two typically-developing siblings (control group) provided data via online questionnaires. Both diagnostic category and autism symptom severity were tested as possible moderators, but neither produced significant interactions with either externalizing behaviors or internalizing symptoms in the target child when predicting externalizing behaviors, internalizing symptoms, or social problems in the sibling. However, across the overall sample (ASD and control groups), maladjustment - particularly internalizing symptoms - in the target children significantly related to maladjustment in their siblings. Thus, these findings suggest that having a sibling with an ASD is neither a risk nor protective factor for maladjustment among typically-developing siblings above and beyond the relation between maladjustment among siblings in general. Given some of the mixed findings in the literature, other possible moderators that may put siblings of a child with an ASD at specific risk should be considered in future research. (C) 2011 Elsevier Ltd. All rights reserved.