I thought the song "Swing low, Sweet chariot" went:
"Sweet n'low, sweet Harriet"
I thought they meant some girl Harriet was as sweet as sweet n'low. Man, was I dissapointed when I found out the right lyrics.
A childhood belief about misheard lyrics

others believed things like this
- I thought God drove a car like ours - a Honda. The song DID say "fill the heavens with sweet Accords..."— Dummy
- I used to believe that "unsavory" meant "sweet".— unsavory
- When there was an advert for a "3 peice suite" i thought it was a shop selling 3 P Sweet's!!!— Kate Parker
- i had a really sweet tooth and i asked my mum when it would fall out...— saza bob
- i get bit by so many moskitos because i'm a sweet child with sugar in my vains.— Ella
- That if you wet a sweet wrap and put it in the freezer overnight, you'd get chewing gum.— Roxie van Renbsurg