When I was little, our cat had kittens, which she kept for a while in a cardboard box that we provided for her. Since I heard the kittens collectively called a litter of kittens, I called the box a litter box. Several people laughed at me at the time for that, and I had no idea why. Later when I learned what a litter box is, I found it very curious that cats have litters of kittens, but a litter box is what cats poo in. In fact, I STILL find it curious.
A childhood belief about cats and dogs

others believed things like this
- No littering $500 fine
I better litter so I don’t get fined!!Anon - When my daughter was 3, she saw a cat using a litter box. She thought it was building a sand castle.— Debbie the Bad Swimmer
- I use to believe that if I baptised kittens they would go to cat heaven.— Edward
- I used to believe that kittens came from pussy willows.— hope
- I used to believe hampsters were miniature kittens and that when they bit me i would be poisoned.— Dylan McDonald
- I used to believe that newborn babies didnt open their eyes for a few weeks like kittens :) — Cash