At some point when I was little, I had some eye-related illness, and there was one time when my eyelids got sort of glued together. Because of that, I was afraid to keep my eyes closed too long for some time. But I knew people slept with their eyes closed. So at night, I would periodically close my eyes for a short amount of time, thinking that it would be enough. I remember some dreams from that time, though, meaning that proper sleep eventually set in.
A childhood belief about sleeping

others believed things like this
- I used to think that if I closed my eyes other people couldn't see me.Anon
- I used to think that blind people always had their eyes closed.Anon
- I used to think that all people closed their eyes and stuck their tongue out when they died.Anon
- i used to believe that if you watched TV for a long time, your eyes would turn into squares.Anon
- I used to believe that when I closed my eyes, nobody could see me. — Jens
- I used to think if i closed my eyes noone could see meAnon