I used to think my mum really meant it when she said "it's raining cats and dogs". I still can't help imagining cat and dog rain every time I hear that expression!
A childhood belief about weather

others believed things like this
- My sister and I thought cats and dogs were the same animal, the dogs were male and the cats were female.— Paul
- I used to believe all dogs were male and all cats were female. I still call dogs "boy" and cats "girl." — Kelly F.
- I use to believe that cats and dogs were the same species; cats were girls and dogs were boys.— poopcrystals
- i used to think tha if you went outside when it was acid raining the rain would burn holes in your skin— fear of rain
- I used to believe that if it was raining, it was raining all over the world at the same time!— stuart bradley
- I used to believe that dogs ate cats.— Tom