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https://www.petmd.com/sites/default/files/styles/slide_show_840_574/public/cat-litter-habits-change.jpg?itok=o_N_YITX

Why is a group of baby kittens called a "litter" and then the same word is flipped to denote the stuff they pee and poop in, throughout their lives if they live indoors? 🤔