I dont know what the heck is wrong with these little monsters! Lately they've taken to going potty on my couch! I clean it, I discipline... I make sure they go out plenty, and they can go when ever cuz I have a dog door... One is a year, the other is 10 mo. Male is fixed, but he's the one doing it! Any suggestions? I have never had a dog that I couldn't potty train, and these two were but suddenly not!