Well this isn't my misheard lyrics, but my sister's. When she was around 4, she was singing "Away In A Manger" at a Christmas party.
"Away in m-m-mary, no crib for a bear"
It's become a family favourite!
A childhood belief about hymns

others believed things like this
- When I first heard Stawberry Fields Forever, I misheard the lyrics as Strawberry Fields For Trevor.— Matt
- I similarly thought that "Proud Mary" included the lyrics "pumped a lot of tanks down in New Orleans."— Larry
- when I was little my uncle told me he was part bear. I believed people could be part bear until I was twelve. — Audrey
- in the song with the lyrics "take your passion" my sister used to always think it was "take your pants off"— Steped
- I used to think virgin mary was actually 'virginia mary'Anon
- I believed that Jesus Christ was the son of the Christ family, i.e., Mary and Joseph Christ.— David Araújo