I used to believe that if you farted when it was cold it would look green instead of the normal steam that your breath makes.
A childhood belief about farting

others believed things like this
- i was scared to fart outside in cold weather because i thought u would be able to see the steam.— xJeNneSceNcEx
- i used to belive when i farted green gas came out my bum— daniel rowan
- When you farted, green air came out of your butt— Yvonne
- That only men farted. I literally started sobbing the first time I realized I farted.Anon
- If you hold your breath and make a wish under a highway tunnel it will come true....I still hold my breath :)— aj
- When I was a child I used to believe that the steam rising from my food were ghosts. Anon