Will an Only Child Struggle to Read Others' Minds? Two Twists in the Research on Siblings and Mind-Reading

A study of 109 children aged 3–6 in Wuhan, China found that only first-borns — not all children with siblings — outperformed only-children on theory of mind. And the only-child gap closed after just two weeks of a short language-based intervention, suggesting it was never a fixed limitation.

June 15, 2026 · 7 min