Some brains do create them. Mine did. I had one for several years, although I learned quickly it was something I needed to keep private. Little John Deerfoot was the recipient of a great deal of my childhood chatter about life. I was home schooled (alone) for K - Grade Five. No surprise, my imaginary First Nation child was very helpful in that one-person school. One of these days I'll write a book about our "adventures of the mind." Even today as I write this, he is as clear is my mind as if he was standing right in front of me, with his jet black hair, beaded headband, single feather stuck in the back, and buff deer-skin clothing. With lots of fringe! Actually, it's been decades since I thought to call up his memory picture. I did last week when a parent asked me, with obvious concern, how to "make a child stop lying about a pretend friend." I suggested the parent let it go, perhaps making a comment now and then about the difference between seeing and touching a person in real life and accomplishing that in the brain. The reality principle--even knowing the difference between imagining and pretending versus what is tangible and concrete--appears to kick in some time after the age of four. The power of imagination is a mental faculty built into the brain (likely in the right frontal lobe). If it has been developed, imagination can help you to plan, envision, create, innovate, invent, set and achieve goals, and so on. Without it, I believe a brain can be handicapped in thinking ahead and figuring out what something may be like and what the person will need to do or bring with them.