I have a three month old pitbull. Don't laugh but I have two chihuahuas female that are potty trained well. When I brought Chino home, the Pit, peed in the house twice. After that he started going outside as trained. We were very pleased and proud. I brought him home when he was six weeks old. He is now three months and the past two to three weeks he has been going in the house. I don't understand how he can unlearn what he was taught. Puppy pads worked for none of the dogs. What in the world is going on. I need a concrete thing here. Please can anyone give me any insight?:confused: