I was always certain that there was either an alligator or a shark in the plumbing of my bathtub. I used to tell them stories while I was taking a bath to make sure they didn't eat me. I think I was in my late teens before I stopped worrying about it.
A childhood belief about bathrooms

others believed things like this
- I used to think that when I was in the bath I shark lived under the bath and that ig might come up and bite me— ------------
- I used to believe that once you pulled the plug in the bath a shark would swim out of the drain and eat you.— Amy
- I used to think that a "pool shark" was an actual shark that lived in a swimming poolAnon
- I didn't know Reindeer existed, I thought they were just christmas animals for storiesAnon
- I once believed that the walls and ceilings were completely jam packed with plumbing and wiring.— David
- I used to believe Gatorade was made from alligator pee.Anon