I didn't actually believe this myself, but it would be funny if children believed that looking in funfair mirrors meant that you really had lost or put on weight!
A childhood belief about magic tricks

others believed things like this
- I'm scared of mirrors because I think that there are ghosts in mirrors— est
- one of my friend's was told by his father that if you didn't turn mirrors over the reflection would run out.— pri
- When I was five or six, I was worried that I'd lost my heart because I didn't hear it beating.Anon
- I thought it was impossible for anyone to lift more than their own body weight. Just seemed to make sense..— Xenomorph
- I believed that I had a fake right big toe, having lost my real one in the plug holder (thanks Helen!)— Mike
- Turtles can fly. I believed it for ages.
My turtle got lost or probably died and I was told it flew away.Anon