What describes the findings of research on children with autism spectrum disorder (ASD) in high-risk families?

The findings of research on children with autism spectrum disorder (ASD) in high-risk families indicate that younger siblings are more likely to be identified with ASD if older siblings have ASD. This is due to a fundamental understanding of genetic and environmental factors that play a role in the development of ASD. When one child in a family has ASD, the likelihood of another sibling being diagnosed with the disorder increases significantly, highlighting the heritable nature of ASD.

Research suggests that families with an existing diagnosis of ASD carry genetic predispositions that can elevate the risk for subsequent children. Additionally, this reflects the increased awareness and improved screening practices for ASD, prompting earlier identification of younger siblings who may present with similar symptoms. Therefore, the presence of an older sibling diagnosed with ASD serves as a critical indicator of potential developmental challenges in younger siblings within the same family context.