I have two cats, and Galen feels the need to play in the litterbox. He's two years old and does this, getting litter and waste *everywhere* in the damn bedroom. I have another litterbox that's covered, but my other cat won't use it because he's too tall. He needs the open litterbox. So is there anything I can do to stop Galen from playing in his box and scattering the litter all over the place? It wastes litter, my money, and I'm tired of my room being covered in litter!