Up until I was 18--18! I believed that there were two kinds of appetizers one could serve at a party--"orderves" and "horse dovers." I had read about "horse dovers" many times in books and magazines, but at all the parties I'd ever been to, they only served "orderves."
It wasn't until I heard a woman on the radio saying that she could never remember how to spell "hors d'oeuvres" that I figured it out. When I tried to spell this word on my own and nothing looked right, the Frenchiness of it all clicked.
A childhood belief about speaking

others believed things like this
- a donkey is just a small horse.Anon
- I used to think that beer was horse pee. Probably because that's what my mom told me...— Kara
- When I was three I used to believe that cow and horse are wife and husband.— xenia
- I used to think giraffes were a type of horse— Crocotta1
- i used to spell eight "ate" cuz of the stuped: why was six afraid of seven, cuz seven ate(8) ten joke...— 8
- I was always told that beer was made from horse pee.— Just me