Examining the role of communication on sibling relationship quality and interaction for sibling pairs with and without a developmental disability.

Matson et al. (2013) watched mixed-ability sibling pairs at play. One child had a developmental disability; the other did not.

They coded who talked, who helped, who argued, and how close the pair seemed. Then they asked if the disabled child’s communication level changed the sibling bond.

Warmth, rivalry, and conflict stayed the same no matter how the child communicated. Love or fights did not rise or fall with speech skill.

Yet siblings gave more help and more directions when the disabled brother or sister could talk on their own. The talking child also spoke more during play.

Hilton et al. (2010) showed that behavior problems, not the ID label itself, drive negative sibling impact. The 2013 paper adds a second lever: communication level shapes helpful acts, not feelings.

Begum et al. (2011) found warmth patterns that differ by sex in teen pairs. The 2013 study widens the age range and shows warmth stays flat across communication levels, so the teen sex effect may fade in younger kids.

Brady (2022) urges broader tools for non-verbal clients. The 2013 data give a reason: when a child gains independent speech, siblings automatically supply more natural teaching moments.

You do not need to wait for perfect speech before targeting sibling closeness—warmth is already there. Focus your teaching on functional communication and watch the typically developing sibling turn into a ready coach. Coach them to pause, prompt, and praise; the play data show they will use these moves once the child can respond.