My special needs cat has kidney disease. I suspect THAT's the reason she was dumped at the shelter. Anyway, one of the complications of FKD is that she doesn't get enough water in her colon to soften up her stool. When I first adopted her, I had to put her in the veterinary hospital to unclog her innards; her stool was too hard to pass. To help her go to the bathroom, I have to give her a mix of water and Miralax twice a day. Plus, what about the water and food? Won't they run out at some point? If she were healthy, I could leave 'em alone overnight with extra food and water. However, with her kidney disease, she needs her laxative every day.