Hypothesis

If imaginary friends are a sign into a childs future, then there could be many undiagnosed cases of schizophrenia, or signs of high intelligence.

To be or not to be...

http://www.seattlepi.com/lifestyle/202632_imaginary07.html

Imaginary Firends in depth

http://en.wikipedia.org/wiki/Imaginary_friend

Imaginary Worlds

http://www.scientificamerican.com/blog/post.cfm?id=imaginary-worlds-are-early-sign-of-2009-08-07

Schizophrenia, Imaginary Friends & Children, Psychology

November 4, 2010

http://wondertime.go.com/learning/article/imaginary-friends_5.html