A developmental investigation of children's imaginary companions.

Twelve 4-year-olds with imaginary companions (ICs) and 15 without ICs were asked to describe and pretend to interact with the IC or a real friend. Children with ICs readily described them and were more willing than children without ICs to pretend the IC or real friend was in the lab. Children were interviewed about 7 months later, and the IC descriptions were as stable as the descriptions of real friends. Children with and without ICs did not differ in their ability to distinguish fantasy and reality, but IC children were more likely to hold an imaginary object instead of substituting a body part when performing a pretend action and were more likely to engage in fantasy in a free-play session