Why Do SO Many Children's Nursery Rhymes End with Something Tragic?

because most of them were not actually written for children, they were poems that talked about what was going on at the time, foe example, ring around the rosie, pockets full of posies, ashes, ashes, we all fall down, this is about the bubonic plaque. ring around the rosie- rash , pockets full of posies-you carried flowers so you could hide the smell, ashes ashes we all fall down-death.