One of my boy friends believed for a long time (27yrs) that a girls periods was white.
A childhood belief about periods

others believed things like this
- When my mom was a child, she thought that while girls had periods, boys had hemorrhoids!Anon
- I used to believe that a long time ago, just like in old pictures, the world was black and white loolAnon
- when I was a kid, I used to believe that only girls could be my friends and all other boys were my brothers.
— rajat - For a long time I believed it was impossible to have sex unless the man was on the top. Anon
- For a very long time I believed that there were little men underground that changed the traffic lights!— Melissa
- I believed for a long time that brown cows gave chocolate milk!— Evil Mom