When I was around 5 I was told that when it rains while the sun is out it means that a witch is getting married.
It rained when the sun was out at my cousin's wedding a few days after I had learned about this. It scared me so badly that 20 years later she still freaks me out a bit.
A childhood belief about witches

others believed things like this
- I used to believe that having children could only happen after a wedding with the person you are married to.Anon
- I used to believe that if it was raining and the sun is outside it's because a witch was getting married.— Jessica
- When I was around four,I used to think when it rained in my area,it rained over the WHOLE world too...Anon
- When I was a kid I thought that when it rained, it rained all over the world.
Anon - When it rained, it rained all over the planet simultaneously— Artgoober
- I used to believe reindeer made it rain because for many years it rained on christmas eve night.Anon