I originally have a miniature schnauzer that's already 2.5 yrs old. This week, I brought home a 4 mo miniature schnauzer. They play fine but the problem is that my older dog has been peeing/pooping all around the house He's never done that and I know it's him because the other dog is in the crate the whole time. I don't know what could be wrong.. Has this ever happened to anyone??