Lead
"I think our child has an invisible friend..." More than a few parents say this with a slightly puzzled look. The companion has a name. The child insists on setting a place at the table. Sometimes the invisible friend is invoked as an explanation for behavior — "Momo is angry, that's why." Faced with all this, parents tend to worry in one of two directions: either something is wrong, or the child must be unusually gifted.
Neither reading fits. Imaginary companions are a common feature of early childhood, and research associates them with positive indicators of social and cognitive development. At the same time, those associations are modest — having an imaginary companion does not make a child exceptional. This article sets out what the research actually says, without inflation in either direction.