I always thought that the operation men get so they can't impregnate a women was the same as when animals get neutered, where their balls are removed. I found out in my late teens though that I was wrong...
A childhood belief about reproduction

others believed things like this
- I used to think sterilised humans were referred to as neutered, in the same way as animals.Anon
- We had a male cat that wasn't neutered. I thought his testicles were just the cat version of a butt.— Robyn
- I used to think that girls had "balls" and not boys, and the "balls" were slang for breastsAnon
- I once had this funny moment as a kid when I accidentally said that my mum was neutered instead of sterilized.Anon
- i always thought it was Grape Balls of Fire instead of Great Balls of Fire— Courtney
- I used to think that oral sex was talking about sex. I was wrong when I found out the truth.Anon