I believe Aliens and Ghosts exist, not positively, but I'm quite sure there's logical enough proof and reasons for believing they might. Especially when I had a ghostly encounter when I was about 8 or 9. Not quite sure what it was at the time, but it scared me. Now I know it was a shadow ghost, but it wasn't against any walls, it was in a 3D spheric form - kind of human like, but not.
It's hard to describe, but I was jumping up and down on my bed which was opposite my door that was in one corner. The lights were off, I think it must have been 12am, because my parents used to put me to bed about 10pm, and I remember staying up late. But anyway, I was jumping up and down on my bed, I don't know why, I guess I used to like bouncing on things like trampolines and beds.
My room was very dark, but my eyes adjusted to it after a little bit. And then I eventually saw the shadowy human-shaped thing right over by my door, and that's when I just paused instantly. It was so quiet I could feel and hear my own heart beating through my ears as I stood and stared at the thing. It was slowly and gradually coming towards me, not changing shape or form.
When it got about halfway across the room, I decided to get under my bed covers. I peeked out of my covers to the side of my bed and it was right beside my bed. The last thing I remember is looking up at it and then just falling asleep. So all in all, it was harmless enough.
The thing that relates to that event, is that the people that lived there before my family had a son, a young man. And he was drunk one night, slipped and cracked his skull on the doorstep resulting in his death. I think my parents said he could have been saved, but no one knew he was outside with a cracked skull on the doorstep until the morning.
Not just that though, other weird things that my mother told me about in recent years. She told me that when I was a child, about 4-5. I used to sit next to the walls and talk to them, having a conversation with someone. I don't remember that, but if my mum said it happened then it did.