My neighbors got a brand new pool one year and we all went over to swim. Before we got in the dad came over and told us "Now, we put a special liquid in the water that turns colors if you go pee in the pool, so don't pee in the pool or we will all know you did it."
I didn't believe him... not completely, but I never peed in his pool either.
A childhood belief about swimming pools
you weren't the only one
36 of you believed this