Talking to imaginary friends helps children develop inner dialogue, private speech or verbalized thought, that can later help them cope with challenges.
Young children's habit of talking to imaginary friends can spur the development of an inner dialogue that they can use to talk themselves through challenging tasks now and later as adults, ...
Children often talk out loud while playing until about age 7, when their outbursts and mutterings become quieter and more internalized, research has shown. This private speech, or verbalized thought, has been shown to improve children's performance on cognitive tasks, such as planning and solving puzzles.
A recent study found children with imaginary friends used significantly more private speech than children without imaginary companions. Conversing with adults helps children develop private speech, the researchers said, and conversing with imaginary beings may serve a similar role.
Interesting and plausible!
It's worth remembering that children don't try to impose their imaginary friends' dictates on the rest of society.