Boys lag girls in language among twins.

A study led by Seyda Ozcaliskan from Georgia State University focused on the role of gesturing in the development of speech, as well as how sex and twinship impact gesture and speech. While gesturing plays an important role in early language development, little research has been carried out on early gesturing in twins. The study compared the behavior of twins and single children, both male and female, among Turkish families.

Language use and gestures lagged behind for twins when compared to single children, and gesture lag reliably predicted speech lag. In both twins and single children, girls performed better than boys in language assessments, however similar improvements were not seen in gesture. Predictably, boy-boy twins lagged the most, with smaller vocabularies and less complex sentences than other groups of comparable age.

This lag in development may be due to decreased parental input: the study showed that the amount and diversity of gestures each child receives is lower, presumably because parents must divide their time and attention between both children. The development of “twin language”—a system of communication often developed by twins—is linked with speech delays in infant twins, meaning the same is likely true for gesture delays. While twins may reach these language milestones later, parents should not worry, as the vast majority of them will catch up by three and a half years old.  Frequent gesturing and naming of objects by parents can aid children’s acquisition of gestures and speech during early development. You can learn more about the study at Science Daily: https://www.sciencedaily.com/releases/2021/05/210510161431.htm