I used to believe that nuns had to hold in their pee for penance. I wasn't even brought up religiously, so who knows where the idea of penance even came in.
A childhood belief about church

others believed things like this
- Mum used to believe there were men, women and nuns and nuns used to have wheels under their habits!— Chris - Sheffield
- I used to think that nuns were God's girlfriends...— Marie
- I used to believe that all nuns were men when I was 4 years old.— SS
- I used to think the nuns were called numbs, and I still don't know why!Anon
- I used to think that Dementors were what nuns became after they died.— Nancy
- I used to believe Nuns are a third gender, a cross between men and women:)Anon