I used to believe that my mother found me in my grandfather's garden and the funny thing is she didn't tell me otherwise until I was about 8 years old.
A childhood belief about reproduction

others believed things like this
- My mother convinced all of us kids in our family that the large rhubarb in the garden was a Man-Eating Plant. — H.Miller
- I used to thing that vikings lived 50 years ago.— Sigrid
- For about 3 years, I thought that chili and salsa were the same thing.Anon
- I believed for years that the sun and moon were the same thing - it just glowed more in the day :)— Deb
- few years ago, finally I found out that asparagus are not big sea fishes.. — nixass
- I thought a "cold sore" on your mouth was the same thing as "coleslaw" and so avoided eating it for years.— Helen (UK)