I thought that when I swallowed gum, it would eventually grow into a large ball of gum on the inside of my belly button, and that I would need surgery to get it removed. I wasn't told that would happen either, some imagination. I'm only 13 years old, just so you don't think I'm some 30 year old believing that would happen. xD
A childhood belief about chewing gum

others believed things like this
- I used to think that if i touched my belly button it would unfold and my belly would be inside out forever. Anon
- If you swallowed a watermelon seed it would grow in your belly— Rachelle
- I used to believe that if you swallowed an apple seed, a tree would grow in your belly.— Rachel
- I used to believe that belly button lint came from the *inside*. Why else would it always be the same color?Anon
- When I was little I use to belief that if we swallowed the pit of a fruit, a tree would grow inside us.— Maya
- I used to believe that If I stuck my finger really far inside of my belly button I could touch my insides.Anon