Question: Should older siblings be routinely tested for autism?
Answer: I mean, certainly older siblings of children with autism are also at increased risk. And, although one would think that an older sibling would be diagnosed at an earlier stage, I think that, you know, what some families face is that you may have two children in the family with autism or other autism spectrum disorders who are very different from one another in terms of their strengths and personality styles, the severity of their autism symptoms, and their level of language or intellectual delays. So, there are situations where there may be an older child in the family with an autism spectrum disorder but who hasn't been diagnosed. So again, I think there does need to be an index of suspicion.
I think that clinicians working with the family should be sensitive to issues around social and communication development in the older siblings. I think the only caveat is that older siblings are not only at increased likelihood of having an autism spectrum disorder, but of a range of developmental and interpersonal challenges that are broadly described as the broader autism phenotype, which really refers to symptoms and traits that are kind of qualitatively similar to the symptoms of autism, but may not be as severe or as impairing. And that includes issues around language development, literacy, social issues, including anxiety and a tendency to have sort of narrow or intense interests, and sometimes differentiating some of these milder traits, from a diagnosis like Asperger's syndrome, where there may be remarkable strengths as well as significant symptoms of autism spectrum disorder, you know sometimes, making the differentiation, it can be somewhat challenging.
So, I think that it may not be as simple as the older sibling sort of getting tested for autism, but rather an open conversation about the types of concerns that the parent may have about that child's social style, kind of social functioning in terms of their friendships, their ability to connect with their peer group, their communication skills and then sort of more mental health issues around obsessiveness or anxiety. And, if that older sibling has any traits that are kind of interfering with their lives, with their social lives, with their ability to learn at school, with their ability to sort of cope and participate in age-appropriate activities, then I think that older sibling warrants a thorough assessment.