I thought that the lyrics for 'Tequila' by Terrorvision were actually 'I want to kill her, it makes me happy..' and I preferred the song when I thought that! I was in my twenties though, so does this count?
A childhood belief about misheard lyrics

others believed things like this
- I thought that Count Dracula was the count from Sesame StreetAnon
- My mum always thought the lyrics to macy grays song was i try to say goodbye to my chook.— alana
- I thought to count to one thousand you did 1-100, then 100-199, then came 1,000.— Anon!
- When I was little i thought that seconds were so fast that you couldn't count them.— Baby
- in the song with the lyrics "take your passion" my sister used to always think it was "take your pants off"— Steped
- i believed that michelle gayle's sweetness song contained the lyrics shade in sheep shit!— andrew