So far so good. Went to vet with Nori (the little black cat) for a check up yesterday and the vet clarified that as long as we keep the cats from eating each other's food, Miso has to eat a special food that helps dissolve remaining urinary tract crystals and we can keep a monitor on his litter box usage he can spend some time with his siblings. So we let them spend a bit of time together but one time Miso tried to lick the floor where the normal food is to try and get his usual food and the other time he didn't want to stay where he needed to and kept trying to get into the container where his crunchies were. So he might only get to go out when Ian's also home to keep the shenanigans to a minimum.