My brother used to believe that "hot yava (lava)" was in the bathroom, especially when you took a shower.
A childhood belief about bathrooms

others believed things like this
- I used to think Tomato soup was Lava.— Daniel Green
- i used to believe lava and water made electricityAnon
- I used to believe that take a shower meant to go steal a shower from the storeAnon
- I used to think that toilets led to the shower head. That's why I never took a shower :D— scared
- I used to believe that if you took a shower after a day of tanning the tan would come off in the shower— Shar
- i used to believe rain was when Jesus was having a shower— matt