I have a 4 year old Chihuaha/Pomeranian mix. He was completely house trained as a puppy but as soon as I moved from the house I got him in he started pooping on the floor. He can be outside for hours but as soon as I let him in and I leave or go to bed he poops on the floor. He never urinates in the house just number 2 and its usually in the same area! Why does he do this or how can I get him to stop??