Sibling Relationships in Adolescence and Early Adulthood With People Who Have Intellectual Disability.

The researchers asked brothers and sisters about their bond with an adult sibling who has an intellectual disability. They tracked the same people from high-school age into their twenties.

The team wanted to know if the relationship got warmer or cooler over time and what changed it.

Feelings grew closer and fights dropped as the siblings moved from adolescence to adulthood. Sharing caregiving tasks made the bond even stronger.

Living in separate homes also cut down conflict.

Alon (2024) and Alon (2026) extend these results. They show that optimism and social support boost positive feelings in siblings of adults with Down syndrome or autism.

Galuska et al. (2006) seems to disagree. It found no adjustment gap between school-age siblings of children with Down syndrome and typical peers. The gap closes when you see the age difference: M et al. looked at kids, while J et al. looked at the same pair after they grew up.

Bhaumik et al. (2008) adds the parent view. Parents saw both strain and strength in the typical sibling years earlier, matching the later warmth that siblings themselves report.

Tell families that sibling tension often eases with time. Encourage shared caregiving now; it is a low-cost way to deepen the bond before parents burn out. When you write transition plans, include the brother or sister as a future caregiver and give them support tools like respite or sibling support groups. The payoff is a warmer, steadier relationship that lasts decades.