I remember when I was a kid, I used to be scared of the dark, I would always need some kind of night light on when I slept in my bedroom otherwise I would panic. I remember once when I was a kid, the bulb in my night light had died and I ended up with no night light due to that, we also had a thunderstorm at the time and I used to be really scared of them when I was a kid. We had a huge flash of lightning and a huge crack of thunder and it scared me. I hid under the covers until I fell asleep but that was a bad experience.
Now that I am an adult, it does not bother me to be in the dark now.