As a professional working with families, I am often asked about imaginary friends. I never experienced this behavior with my own son so I have little personal information to share.
One child required that a place be made for the "friend" at mealtimes complete with chair and food. She scolded people for sitting in her friend's chair or sitting in her place in the car. This lasted for several years. She is now a middle age lady who can tell you the names and description of her friends.
This lady has struggled with relationships and inappropriate behavior over the years. I am wondering if there is any relationship between her imaginative friends and her lifelong behavior.
Should parents "adopt" their children's imaginary friends or discourage their presence? If they should be discouraged, what strategies are helpful?