Whenever my family took road trip vacations I used to believe that the bottles of yellow liquid on the side of the interstate were half drank containers of apple juice.
It was only much later that I figured out they were depositories of urine from lazy truckers.
A childhood belief about drinks

others believed things like this
- as a young child i thought poo was brown from eating chocolate and pee was yellow from drinking apple juice!Anon
- I used to think that apple juice was beer and I'd drink it all the time and pretend to be drunk.— Dee
- I believed that the gap between the double yellow lines in the road was a special lane for motorcycles.— Joel
- My Mom used to tell me if I swallowed an apple seed I would grow an apple tree inside my stomach!— Marg
- I used to believe that an Adams apple was a piece of apple that was stuck in someone's throat.— Ron Aaron
- When I was a kid, I used to bellieve that when I eat an apple pip an apple tree would grow up in my stomach!Anon