When I was little, my mom used to watch the X-Files alot, and once I heard her and my aunt talking about an episode that involved a woman becoming pregnant with an alien or something like that. For some reason I associated this with the toilet, and I thought there was an alien living in the toilet that would come out and get me whenever I flushed. So when I was done, I would stand up, flush, and run like hell for fear that there would be a huge flash of green light and the alien would come and get me. I had an overactive imagination.
A childhood belief about fear of

others believed things like this
- I thought the ball-headed person in the Bic logo was an alien and communicated using alien-like noises.Anon
- Oh oh, I'm an alien, I'm a little alien...
Legal maybe?— Marina - I used to think that green poop ment you were an alien.— fartcheeks
- i thought aliens would come to earth year 2000 because of a commercial were an alien ate a hot dog— ulle
- I used to think that my cat was an alien that had come to teach me how to be good!— laz
- I used to belive that my teacher was a alien unfortunately this was true mum and said. — peter