When I was 5 I used to lay my head down to my brother´s belly to listen to his bowels´ sounds / I now believe many if not every child does this/, but somehow these sounds made me picture the bowels looking like a big nice juicy slice of water melon. Today I am a doctor and sometimes when I am listening to peoples´ bowels sounds with a sthetoscope I recall the picture and have to smile and they don´t have a clue why.
P.S.1: This is another story - but you wouldn´t believe, what many grown people think of what human body looks like and functions inside - this could be a topic for another great site like this.
P.S.2: Excuse my English, I´m not a native speaker.
A childhood belief about general

others believed things like this
- As a child, my twin sister and I used to pronounce `Spaghetti' as `Mastaghetti'. Sounds a bit rude, no? Anon
- I used to believe that the twinkling of the stars made the sounds that crickets made.Anon
- I use to beleive that because oui (which sounds exactly like wee) mean yes in french, that poo meant no.— Toby
- I used to think dogs had hooves, because they make hoofbeat-like sounds when they walk.— Samuel Lamont
- i could swear eleventeen was a number for the longest time -- it still sounds pretty convincing.— erin
- When I was young I thought that police had soft skin, because this is how it sounds in French " Peau lisse "
— amine