I shared a bedroom with my sister and the water tank was in the loft above and it would make shushing noises and I never knew what it was but I thought there were burglars outside our bedroom door whispering shush to each other.
A childhood belief about criminals

others believed things like this
- I knew lightning could come in through my bedroom window and kill me.
— Cyn - I used to believe my bedroom closet was actually a time machine.— Carrie
- I used to think that the TV show "Shark Tank" involved actual sharks in a tank.Anon
- I used to believe that one of Lady Gaga´s songs goes "bedroom ants" instead of "bad romance"— Anon the III.
- I thought that hydrogen was pure water (since I knew hydro- meant water) and H2O was impure some how— Hexetic
- I used to think that there were ghosts in the loft and that's why I was not allowed to go up there.Anon