How does having an Autistic sibling affect toddlers?

During my previous employment at the Australian Psychological Society on the early childhood mental health promotion, prevention, and early intervention initiative, KidsMatter Early Childhood, I developed a keen interest in the well-being of children under school age. I discovered that even during toddlerhood, some children begin to show signs of emotional and behavioral difficulties, including “acting out” difficulties such as aggression, and “holding in” difficulties such as excessive worry and anxiety. Whilst some children “grow out of” these difficulties, around 1 in 2 children do not seem to improve without intervention, and continue to show signs of difficulties when followed up in later years.