I used to believe if you closed the toilet door after using it the toilet would overflow.It must have happened once when I was little and nobody heard the toilet running because I had closed the door!
A childhood belief about fear of

others believed things like this
- I thought that toilet paper was bread and by puting it it the toilet i was feeding the ducks at the bottem.— Gringo
- I used to believe that monsters lived in my toilet and they ate my poop and urine when i flushed the toilet.Anon
- I used to believe that if I flushed the toilet before I showered, I would take a shower in dirty toilet water.— Chris D
- I used to beleve when i was 4 that the flush on the toilet was to wake up toilet monsters.— Millie
- I used to think if I left the toilet seat open my cat would get flushed down the toilet.— G
- My sibs and I thought that the screen door was called the "scream door" so Mom could yell at us through it. — Kyle