Mona told me once that when her twins were little, they used to go to an old dresser at this house they'd recently moved into at night and try to move it. Eventually she moved it and found a huge dark stain underneath. According to the house history someone had been shot and killed in that room.
Cici's little sister used to play in this one sandbox all the time, and she could see her talking to someone. Eventually Cici asked her why she was always playing by herself, and the kid seemed honestly surprised, saying "I never play by myself."
Another time the same kid ran to her mom and told her that Cici had a naked boy at the house, and she was so frustrated with not being able to find him that she started crying. I was there for that one, at the time it was kind of funny..
When I was a kid I'd have screaming fits every night, getting bizarre injuries in the night and talking about people who shouldn't be in the house. That sort of thing is more of a blur to me, but it used to scare people.
I don't make a point of speaking with children, but I've been left with a family friend's kid. When I was much younger, a girl named Miranda needed me to stay in the room while she fell asleep during one of my mom's Christmas parties. She told me there was a pitch black man who watched her from the window, and sometimes if she shut her eyes for too long she'd open them and he'd be standing in the room with red eyes. Could've been one of imaginary things, but she seemed genuinely worried about it.
I've also had the pleasure of trying to explain to one of my aunts that I didn't have any friends with me when I had to babysit for a few hours. Different occasions where the kid said there was a tall man who was always behind me. I was all "WHAT?! I don't have any friends!" >>
That's all I can remember for now.. I never really hang around kids, but I've heard tons of stories from different people about their own kids etc.