Whether they grew up with their mom and litter mates or as an orphan with human care, it's in a kitty's DNA to do their business where they can cover it. That instinct to dig and cover their waste, in theory, translates into them using a litter box.
Toilet training your cat isn't as great as it sounds
How do cats know automatically how to use a litter box? : r/askscience
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How do cats know to use the litter box? How do kittens house break themselves immediately (use the litterbox right out of the gate)? - Quora