When I was 5, I believed I had to pretend I was asleep as soon as I got in bed because a monster (bigfoot like) would come around to check. If he saw you awake through the window, he'd attack you. I could even hear the footsteps on the leaves outside of the bedroom. I later discovered this was the sound of my heartbeat in my ear against the pillow.
A childhood belief about under my bed

others believed things like this
- At nights, when I have trouble sleeping, I used to hear large footsteps - something like the Godzilla.— John
- I knew lightning could come in through my bedroom window and kill me.
— Cyn - I used to beleive that bigfoot lived across the street from me.Anon
- I believed that leaves on trees only became individual when you you close to them, and then I got glasses.— nola
- when I was little I believed that if I put a white stone under the pillow with my tooth I make more moneyAnon
- I believed that the pictures on my nighties came alive at night and played in my room while i was asleep!!Anon