I used to believe that the little kid from "Pet Cemetary" and the real killer (The one dad) from "I know what you did last summer" were under my bed and if I put my feet on the floor too close to the bed when I would get up, the kid would cut the tendon (Or whatever you call it) in my heel just like in the movie and the "I know what you did last summer" killer would pull me under and chop me into little bits.
A childhood belief about under my bed

others believed things like this
- When I was little, I used to think that a serial killer was a killer who ate a lot of cereal.— believe
- the summer that I turned 11 I waited out side on the step all summer for my hogwarts letter... ;D — Ginny weasley... not really
- I used to think the lyrics of "Boys of Summer" said "poison summer"— Lindsay
- I used to think i was a serial killer because i ate cereal!— Mikita Jones
- I thought that my dog was a killer dog that was undercover and that he was like a spy or something— Laura
- I used to think a serial killer was golden grams...— weird