When I was younger, I used to think when my mom said "P.O. Box" she was really saying "Pill Box." So I wondered why she would call it as pill box as if there were medicine pills in there when there was only mail. Just recently am I finding out that it's pronounced Pee-Oh box.
A childhood belief about speaking

others believed things like this
- Until very recently, I thought "archives" was pronounced like "are chives".— Mitsuki
- i used to think that the word e-mail was a sex, like male, female and e-mail.
I'm so thick!— Confoozed - When i was younger i thought R.I.P on graves was a persons name, i always wondered why so many Rips died. — Jess
- When I was younger I cut my Barbie doll's hair and wondered why it never grew back.Anon
- I used to honestly think that Smarties were medicine.Anon
- I thought when i was a kid, that all mailboxes had tubes that brought your mail to the person u sent it to.— Andrew