Watching a video together creates social closeness between children and adults.

Human social relationships are often formed through shared social activities in which individuals share mental states about external stimuli. Previous work on joint attention has shown that even minimal shared experiences such as watching something together facilitates social closeness between individuals. Here, we examined whether young children already connect with others through joint attention. In the current studies, children sat next to a novel adult who either watched a film with them or was not able to see the film and read a book instead. After the video, we measured children's willingness (i.e., latency) to approach the experimenter holding out a toy. In both studies, the 2.5-year-olds who watched the film together approached more quickly than the other children. These results show that both minimally interactive shared experiences and noninteractive shared experiences lead children to feel more comfortable with a novel adult. This suggests that joint attention interactions, and shared experiences in general, play an important role not only in children's cognitive development but also in their social development and the formation of their social relationships.