A childhood belief about weeing and pooing

When I was younger I had chronic bladder and urinary tract infections which made me have accidents even while in elementary school because I would hold it as long as I possible could due to it being painful to pee, which also attributed to a pee-pee dance you could find me doing often.
I went through a stage where I didn't wear underwear to bed and thanks to my three older sisters who didn't want to have to share a room with a non-underwear wearing little sister while our house was being remodeled, I used to believe that if I didn't wear underwear to bed little elves and dwarfs, the size of specs, would crawl under my blankets and pajamas at night to build cobwebs so I would never be able to pee again. I would cry and cry and cry because I thought I would always have a full bladder and since I could never pee again, I was told I would always have the pain that came from my bladder problems. Needless to say, I was too scared to remain stubborn and they got their way, underwear it was. I'm still a little worried to go without.