All of a sudden (since Dexter's tennis ball incident), Kirby is starting to be a bit of a brat. He has started to refuse to go out back to go potty unless one of us goes out with him. This just started since Saturday. This morning I literally picked him up, put him outside and shut the door. He just ran from one door to another. He somehoe managed to open the back door into our house and I find him standing next to me (tail wagging). Any advice? We do not make of habbit of sticking them outside themselves to entertain themselves, but he has always just gone to do his business on his own.