I used to think it was the greatest coincidence in the world when they would have the Jetsons episode where they traveled back in time and met the Flintstones. "What are the odds of my two favorites cartoons families traveling through time to meet each other?" I thought. It was only later that I realized Hannah Babara was masterminding the whole thing behind the scenes.
A childhood belief about cartoons

others believed things like this
- We knew a woman named Barbara Hannah, and I thought she was was in charge of Hannah-Barbara!Anon
- I used to believe that every country in the world had the same time. Guess I didn't consider time zones eh?— what are time zones again
- Because of cartoons, I thought that to drive you'd just turn the steering wheel back and forth constantly. — Mitsuki
- I used to think Hannah Barbera was one woman...not two men. I didn't figure it out until I was about 15!— minkie
- When I was little I used to believe that God looked like the Great Gazoo (the alien from "The Flintstones").— Susan
- I used to believe that the video clip are realized in one time and the singers are singing with to the music Anon