I used to believe that everyone only had Uncle Bills and Aunt Sues. My mother had a brother named Bill and a sister named Sue - and Sue happened to marry a man named Bill. My father had a sister named Sue as well. So I had two uncle Bills and two aunt Sues. When a friend told me he had an Uncle Pete (or some such non-Bill name,) I didn't believe him, because ALL uncles are "Uncle Bill."
A childhood belief about family

others believed things like this
- I thought Oklahoma was named after my Uncle Homer. (Pre-Simpsons)Anon
- The boy in my class named "Sahand" must have a sister named "Safoot".Anon
- I used to think Uncle Ben and Aunt Jemima were a married couple. — l stu electtirc boogaloo
- I used to think that Bill Murry and Tom Hanks were the same person.— Andy
- when i was growing up i had two imaginary friends. One was named Jennifer, the other was named Onion.— Tessica
- I used to believe there was a Russian Leader named Garbage Trough and an Arabian named Are A FatAnon