This is not exactly what I believe, but an example of the cruelty that older siblings inadvertantly inflict on their younger brethren.
My mum was studying psychology A'level when I was about 15. I had a younger brother - aged 3. He was really naughty and I was sick and tired of him getting to watch all the cartoons when I wanted to watch other stuff.
I read my mum's psychology textbook and came accross the idea of conditioning. I reasoned that my brother didnt know any different and so I could just tell him that news programmes were, in fact, cartoons. If I did it often enough then he would get the message and I could watch all the TV I wanted. For two weeks I stalked the little imp and kept telling him that news was cartoons and vice versa. Naturally, he wasnt having any of it and would scream blue murder whenever I turned over from a cartoon to the news and told him that I was giving him what he wanted.
Eventually my mum found out and grounded me for a week.
I'm now a clinical psychologist and my brother is an IT consultant. Need I say more...
A childhood belief about cartoons

others believed things like this
- I thought cartoons were real, I remember asking my mom why there were lines around the "actors" in a cartoon.— Steven Graziano
- I used to believe that one day, my younger brother would be older than me and then he'd pick on me!— Andrew
- my older brother told me that if i didnt clean every bit of dirt out of the prints on my feet, i'd die— chel
- i used to belive in cartoons— morgan
- if you broke the glass on the tv, the cartoons could come out, or you could go in there with themAnon
- I used to wonder why people didn't have outlines like they did in cartoons.— Anna