When I was a pre-schooler, my older brother made me promise never to drink cold liquid from mugs (rather than glasses), as it would dry my mouth out and make me be sick. I still feel uncomfortable if I am obliged to drink anything other than tea or coffee from a mug.
A childhood belief about drinks

others believed things like this
- I used to think it was illegal for children to drink coffee— C.W.
- I always thought there was a drinking age for coffee, because it was an adult drink like beer and wine.Anon
- I used to think that if you mixed a diet drink with a regular drink, it would explode. Anon
- I thought Pink's "You make me sick" was "you make me sick, you make me look like a candlestick" LOL— Rice
- That you had to be a male to drink beer.— andrei gaspar
- I used to believe that you needed a prescription to drink Dr. Pepper.Anon