As a small child, my father always called me "Boog-a-loo" for some unknown reason. He's also been a fan of Nirvana for as long as I can remember.
Whenever he'd sing along to the song "Lithium" in the car he'd sing "I'm so ugly, but that's ok / cause so are you / Boog-a-loo". The correct lyrics are "I'm so ugly, but that's ok / cause so are you / we broke our mirrors"
I'm now a fan of Nirvana, and almost 15 years later, I still sing the wrong lyrics out of habit.
A childhood belief about misheard lyrics

others believed things like this
- Did anyone else sing "Hark, the hairy angels sing"?— Jill
- My mum said that when I used to sing "noahs arc" at school I would sing "who built the arc, no one, no one"— Clare
- Does anybody remember that song "OUT OF REACH" well i remember i used to sing it as "BATTEERRRRYYY". — meeeeeeeee
- I used to think it was true that only ugly girls poop and I thought I was an ugly girl because I poopedAnon
- The Kim Carnes song called 'Bette Davis Eyes' well my dad used to sing "She's got Dickie Davis Eyes" Anon
- I thought that singer/songwriter was spelled this way: sing-a-song-writer...Anon