When I was a child, I had this painting in my room. It was two children, a boy and a girl, playing hide and seek around a tree- sort of chasing each other around the tree trunk IYKWIM? You couldn't see their faces.
Those children used to move. The boy would disappear behind the trunk of the tree, as if he was catching up on the girl, then he would take the girl's place and she would disappear. Then they'd go back to normal. This wasn't a corner of the eye thing, I used to sit and watch them do it. The painting hung in my room for years, and the children would move probably once or twice a month. I kept mentioning it to my mum, and eventually I think she got rid of it, because she was freaked out. I've never seen a copy of it since
Other stuff happened in that room too- my door would open and I'd see a shadow move, as if my mum was coming in to check on me, but then nobody would appear, and I'd hear both my parents coming up the stairs ten minutes later. And I always felt that someone was standing at the end of my bed- I could almost see them, you know when you can tell someone is standing in the dark, because the darkness looks sort of darker?
Years after we moved out of the house, we found out that a friend's aunt had lived in the house for years. In the 50's, her only child, aged 5, had died in the night- an underlying heart problem I think it was. In my room.
I've told DH and a few friends about that bit, but I've never told anybody about the picture