Considering the fact that have never believed in ghosts this is going to sound strange (even to me) but we have a ghost in our house. Used to have two, but we managed to make one of them , a child go away after a friend of ours Grandmother exercised our house. She was visiting from Ireland where she is highly regarded as a Shaman. I know this sounds like a bad movie but we had a child ghost that would turn on cartoons in the middle of the night, play all of the loud obnoxious toys that kids have etc. Did I mention the fact that all of the toys and tv are downstairs, while all of the people are upstairs? The other is an old man. My DS has brought him up several times, asked me once why he never comes downstairs. Everyone in the house has seen him on more than one occasion. And I still don't believe in ghosts!
The second thing is that although all kids have imaginary friends at some point, my son seems to have a special relationship with his. He's very matter of fact that his friend is around, has no problem with the knowledge that no one can see him and has maintained this friendship? for over 3 years now. He only interacts with "Juice" at home and when questioned he replied "Juice can't leave the house." I've always found this a little unnerving from a child who sees the entire world in black and white. He is as a rule an extremely logical kid. He didn't care for Harry Potter because "it couldn't be true".
As far as God goes... His words "The jury is still out"