I used to be believe that, in public restrooms, when you flushed the toilet, the lights would go out (and you wouldn't be able to find the way out of the restroom, etc.). Then, one day, it happened. Seriously.
A childhood belief about fear of

others believed things like this
- 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 think if I left the toilet seat open my cat would get flushed down the toilet.— G
- I used to believe that the toilet would suck me down if I flushed it.— :-)
- i use to believe that if i flushed the toilet when i was still on it would suck me down to who knows whereAnon
- I don't know why. But I always ran away screaming after the toilet flushed.— Bijan