According to a new study, published in the journal pediatrics, nearly one in five kids with an autistic older sibling could develop this developmental disorder, CTV reports. The study looked at over 650 infants with at least one older sibling with autism, and found that 19 per cent of them—132 of the infants—were diagnosed by age 3. But among those with more than one older sibling with autism, 32 per cent were diagnosed. The study was conducted across the U.S. and Canada. Researchers suggest genetics could play a role, and encourage parents to screen siblings of autistic children.