One time we had a huge storm, so we brought all the
cats in (they slept at that time
in boxes
in a mostly-enclosed porch, but for some reason that didn't seem like enough) and our two Golden Retrievers. Set out the dog beds, set up the cat sleeping boxes, put the animals in the room. One by one, each cat went over, sniffed the dog's bed, and peed in it. Can't remember now if they picked on one dog, or if they shared the bounty between both beds.