Cats can bother each other just fine without any help from stupid humans–especially while they’re eating. Don’t be like some of the gavones in this video who bug their cats at mealtime.
I was going to suggest, “Yo, Steinmetz–you got two cats, serve them their food on two plates.” That’s what we do. Except our cats have developed this weird custom of changing plates two or three times during their dinner. No, they don’t move the plates. Eat off one for a minute, then drive your sister off the other one so you can eat off that one while she eats off the plate you just deserted. It’s very complicated–a cat thing, I guess.