When I was little, I was wondering how girls peed, so I asked my mom, and she told me that girls peed out of their butts. I believed this for a few years, until I was 8, when I was at a female friend's house, and I said something that revealed this belief. She told me that this was false, and although she wasn't at all scornful, I was horribly embarrassed. Later that day, I asked my mom about it, and she said that girls pee out of their vaginas.
This, of course, is also false.
I learned the truth from internet porn when I was 12.
A childhood belief about weeing and pooing

others believed things like this
- When I was a kid I thought girls peed out of there vaginas...woops!— Greg
- When my brother was little, he believed that girls peed out of their boobs.— Emily
- I used to think girls peed from their butt.— Neil
- I used to beileve girls peed out their butt 😂Anon
- I thought that the difference between girls and boys was that girls have teeth.
Anon - In first grade a boy told me that he could see girls naked with his microscope lens. I beleived it for years.— Jeanette