My church has a traditon; every Sunday morning, everyone who has had a birthday during the week goes to the front of the church while the congregation sings 'Happy Birthday' to them. Only we had a slightly different version of Happy Birthday to make it 'church appropriate'. It went; "Happy Birthday to you, happy birthday to you, god bless you and keep you, another year through."
I thought until quite recently 'God bless you and keep you' was 'God bless you, Ankie Beau'. I figured 'Ankie Beau' was another one of those weird, archaic phrases like those in the hymn book.
A childhood belief about misheard lyrics

others believed things like this
- My parents have the same birthday -- month, day, and year. I though all mom's and dad's had the same birthday.— Cait
- Up until I was almost 11, I thought that a birthday suit was a special outfit you wore only on your birthdayAnon
- I used to think that a birthday suit was a special outfit you wear on your birthday— Bri
- I used to believe that on your birthday, you didn't advance to your next age until you ate your birthday cake.— Casi
- I used to think that everyone's birthday, including my own, always had to be on a Sunday.Anon
- i thought I got one year older when my family sang the birthday song.— I am the ghost