I can't say yes or no for sure on possession. My dad swears that possession is a real thing. My mother was diagnosed as multiple personality, this is in the 70's so it was syill diagnosed as that. My dad said when her alter took over that she was possessed by a very powerful demon. When I started exhibiting symptoms of schizoaffective, hearing voices and seeing things and other odd symptoms, he said that I had inherited her demon. When my son started showing signs of the same disorder as myself and started getting into a lot of trouble with the law, my dad said that he had an even more powerful demon. I know that when I am on my medication right I don't see things and don't always hear the voices. I have seen my son on medication and he is just a normal young man then. My dad is very devout in his beliefs. I don't knock them. But I don't have to completely agree with him. I can see why he thought my mother was possessed, when her alter took over, her eyes changes colors, her voice changed, her accent changed, she wrote with the opposite hand, and she dressed and behaved different.