I currently have a litter robot. I have two cats that are polar opposites. A thin and lanky and then I have Dax. Dax is nearly four years old. He was considered a referral cat, they clipped his ear. But my main concern is that he's overweight and current litter gets off track and then he has litter stuck to his paws or tail. Never poop. I feed a can of wet food every morning and Dax and the other cat share it along with a bowl of dry for the rest of the day. Can this litter box help accommodate the size difference of my two cats. And is it his weight that is causing this to happen.