Invisible friend(?)

I understand that many children have invisible friends at some point in their childhood. Sam is putting a new twist on the idea though. Sam has invisible MONSTERS. Usually they are friendly and he wants them to come with us wherever we are going. In fact we had a monster come to church with us tonight to do the Stations of the Cross. He as wonderfully involved conversations with the monsters. They often end up in time out because they are being bad.