Birth order rank as a moderator of the relation between behavior problems among children with an autism spectrum disorder and their siblings.
Big-sibling autism plus acting-out equals trouble for the little one—watch that younger child closely.
01Research in Context
What this study did
The team asked parents about behavior in both children. One child had autism. The other child did not.
They wrote down who was born first. Then they checked if birth order changed how one child’s problems affected the other.
What they found
When the child with autism was older, his outside acting-out predicted more acting-out in the younger brother or sister.
When the child with autism was younger, the link disappeared. Birth order acted like an on-off switch.
How this fits with other research
Hastings (2003) already showed younger brothers and sisters of kids with autism are at extra risk. The new study says the risk is bigger only when the autistic child is the older one.
Schmidt et al. (2013) found most clinic-referred Asperger cases are first-borns. That seems opposite, but they studied who gets diagnosed, not how siblings influence each other.
Hastings (2007) tracked families for two years and saw child problems spill over to siblings later. Levin et al. (2014) now show the spillover is instant when the autistic child is older.
Rixon et al. (2022) split autism into sub-groups and found conflict is worst when the autistic child shows high outside acting-out. Birth order and behavior type now both matter.
Why it matters
Check the birth order in your intake form. If the client with autism is the big sibling, keep an eye on the little one. Add social-skills practice or emotion coaching for that younger brother or sister before problems grow.
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02At a glance
03Original abstract
Variability within the literature investigating typically-developing siblings of children with an autism spectrum disorder suggests that the quality of sibling outcomes may depend on specific factors. For this study, 42 parents of a child with an autism spectrum disorder and a typically- developing sibling provided data via online questionnaires. Birth order rank of the child with an autism spectrum disorder significantly moderated the relation between externalizing behaviors in children with an autism spectrum disorder and externalizing behaviors in their typically-developing siblings. Children with an autism spectrum disorder and higher levels of behavior problems had typically-developing siblings with higher levels of behavior problems only when the child with an autism spectrum disorder was older. These results provide a hint of clarification about the complex nature of sibling relations, but a great deal more research is needed to further examine outcomes of typically-developing siblings of children with an autism spectrum disorder.
Autism : the international journal of research and practice, 2014 · doi:10.1177/1362361312458185