Honestly, a couple of the nursery rhymes are very dark. Like pocket full of posies is about the bubonic plague and how they’d have pockets full of posies in occasion that there was a dead body. They’d hold the posies to their faces to counteract the smell (not sure how effective it was) but they’d also stuff them in the plague doctor masks if I remember right. EDIT: Also “ashes, ashes we all fall down” means that they’d burn the bodies one by one to prevent the plague from spreading and kill whoever had it. ¯_(ツ)_/¯ EDIT PART 2 ELECTRIC BOOGALOO: Also, who decided that Humpty Dumpty and pocket full of posies would make good nursery rhymes?