This isn't quite a belief, but when I was very young the only movie I'd watch was Disney's Beauty and the Beast and all I would wear was dresses. Whenever my mother bought my a new dress, I would be immensly proud of it, and walk up to strangers in the grocery store checkout line and proclaim "Dis is my Booty dress!" and spin around for approval. (I could not pronounce Beauty).
When I got home after buying a dress, I would go infront of a mirror and tell my mother "I Booty!" I never relized until recently what people found so funny about that phrase.
A childhood belief about appearance

others believed things like this
- my mom told me that if i went inside the dresses at the clothing store, the dress would eat me...Anon
- When I was about 5 or 6, I used to think the song 'Beauty and the Beast' was really 'Beauty and the Beef'.— Natski
- I used to believe that Madonna's "dress you up in my love" was "dress you up in nylon."Anon
- when i was young i thought the if i would dress up as a transformer i could fly to school on haloween— ben
- I belived that when I took a crap, my turd(s) would turn into snakes and bite my booty.— Butters.
- I used to believe that beauty marks (freckels) were Butterfly bites!— Jolene