When I was about 6 I read something in a magazine about how people of a certain culture (no idea which) believed that if you slept with your mouth open your soul would climb out and you would stay asleep forever... this scared the hell out of me and I couldn't go to sleep for ages because I was too afraid my mouth would fall open!
A childhood belief about sleeping

others believed things like this
- I used to believe that if I slept with my mouth open that spiders would crawl in there and live in my stomachAnon
- my brother told me that if i ride my bike with my mouth open i will swallow my tounge. Anon
- I was told that if one doesn't cover their mouth when yawning that their soul would escape.Anon
- I thought vegetarians couldn't read Chicken Soup for the Soul. — Aretia
- I used to belive that if i put my foot in my mouth, I would get foot-and-mouth illness— Emily Sathrota
- When I was little my friend told me that if you snease with your eyes open you eyes will fall out!Anon