When I was around five, I caught a glimps of a scene from a scary movie from the eighties where something came up from a toilet and grabbed the girl sitting on it.
For a very long time I thought that was possible, especially after hearing about snakes turning up in toilets in FL.
A childhood belief about fear of

others believed things like this
- I used to think you could get pregnant by sitting on a toilet seat.— Lisa
- I used to think that my dad was "smoking pot" when he would smoke his pipe while sitting on the toilet. Anon
- I thought Buckwheat from "The Little Rascals" (1994) was a girl because he had long hair!— Molly
- I once thought that snakes had legs like a centipede.Anon
- I thought all snakes were venomous and you always die if you get bit by a snake— Elviessa
- I used to believe that if I sat on the toilet too long a snake would come up and bite me.— Cheesemonkey