Summary: Twin children tend to be slower than single-born children in both gesture use and early language development. Within twin pairs, girls show a small advantage over boys in early communication.
Source: Georgia State University
Gestures—like pointing or waving—often appear before a child’s first words, and new research from Georgia State University shows that twins produce and use those gestures less than single-born children do.
Seyda Ozcaliskan, associate professor in the Department of Psychology and the principal investigator, reports that twins both produce fewer gestures and point to fewer objects compared with singleton children. The research also confirms previous findings that girls generally develop language skills earlier than boys; this sex difference appears in language but not consistently in gesture.
“Gesture and speech develop together in early childhood, and when one lags the other often follows,” Ozcaliskan said. “Our findings suggest that monitoring a child’s gestures gives useful clues about their upcoming language milestones.”
Across the studies, reduced gesture use reliably predicted delayed speech milestones, while frequent gesturing tended to indicate that speech would soon follow. Parents can encourage early language by naming objects their children point to and by pairing words with gestures.
One likely reason twins show reduced gesture use is lower parental input. In the analyzed interactions, parents of single children used a wider variety and larger amount of gestures than parents of twins. Ozcaliskan suggests that caring for two infants divides parents’ attention and shortens interaction time with each child, which reduces opportunities for gesture-rich exchanges.
The research team included Ozcaliskan, doctoral students Ebru Pinar and Sumeyra Ozturk, and collaborator Dr. Nihan Ketrez in Istanbul. They analyzed video recordings from Turkish families, comparing three twin dyad types—boy–boy, girl–girl and mixed-sex pairs—with singleton boys and girls and their parents.
Prior work had already shown sex differences in early vocabulary: young girls typically produce more words and more complex sentences than boys of the same age. Twins also begin behind singletons in early vocabulary and sentence complexity, but most of these differences remain within the range of typical development and resolve by about three and a half years of age.
Gesture has received far less attention in twin studies until now, even though pointing commonly appears around 10 months—months before most first words. Pointing and other gestures let infants express meanings they cannot yet put into words and support later speech development.
In some cases, twins develop intensive, idiosyncratic ways of communicating with each other—sometimes referred to as a “twin language.” That close, twin-focused interaction can delay exposure to broader parental input and may contribute to slower acquisition of conventional gestures and vocabulary, the researchers note.
Ozcaliskan emphasizes that occasional differences in gesture or early vocabulary are usually not cause for alarm. “Most children catch up by around three and a half years,” she said. However, persistent delay in gesture use may signal a broader developmental or language concern and could warrant professional evaluation.
For parents who want to support early communication, the researchers recommend frequent, simple strategies: respond to a child’s points by naming the object (“Yes, that’s a bottle—do you want your bottle?”), and use your own gestures when you label objects. These practices increase the amount and variety of input children receive and help integrate gesture with speech.
“Gesture is a powerful, early communication tool,” Ozcaliskan said. “Pay attention to what children point at or show, and use clear verbal labels and gestures in response. That combination supports both gesture and speech development.”
About this language research news
Source: Georgia State University
Contact: Anna Varela – Georgia State University
Image: The image is in the public domain
Original Research: Closed access. “Parental Speech and Gesture Input to Girls Versus Boys in Singletons and Twins” by Seyda Ozcaliskan et al., Journal of Nonverbal Behavior. Also related: “Effect of Sex and Dyad Composition on Speech and Gesture Development of Singleton and Twin Children,” Journal of Child Language.
Abstract
Parental Speech and Gesture Input to Girls Versus Boys in Singletons and Twins
Previous research shows early sex differences in speech development: girls typically produce a greater number and wider variety of words than boys at the same ages. Gesture differences have also been reported. Parents often vary their speech when interacting with singleton sons versus daughters, but it has been unclear whether such variability extends to parents of twins or to parental gesture input.
This study examined parental gesture and speech directed to 35 singletons (19 boys, 16 girls) and 62 twins (10 boy–boy, 9 girl–girl, and 12 mixed-sex dyads) in Turkey, with children aged approximately 10 months to 3 years 4 months. The analysis asked whether parental input differed by child sex (girls vs. boys), by group (singletons vs. twins), and across twin dyad compositions (girl–girl, boy–boy, girl–boy).
Results showed little evidence that parents adjusted their speech or gestures based on child sex or twin dyad composition. However, there was a clear group difference: parents of singletons provided more gestures overall, and a greater diversity and complexity of gesture, than parents of twins. These findings suggest that differences in parental input to singletons versus twins may first appear in gesture, with potential downstream effects on children’s early language development.