Parallel Play

Parallel play is a form of play in which children play adjacent to each other, but do not try to influence one another's behavior; it typically begins around 24–30 months.[1][2] It is one of Mildred Parten's stages of play, following onlooker play and preceding associative play. An observer will notice that the children occasionally see what the others are doing and then modify their play accordingly. The older the children are, the less frequently they engage in this type of play. However, even older preschool children engage in parallel play, an enduring and frequent activity over the preschool years. The image of parallel play is two children playing side by side in a sandbox, each absorbed in their own game, not interacting with the other. "This is considered an early stage in child development, characterized by egocentric behavior and the inability to decenter and coordinate with the activities of a 'playmate'". https://en.wikipedia.org/wiki/Parallel_play