Gus had a bout of bad diarrhea last week where he had some accidents around the house (mainly by the front door), and I didn't punish him as I figured he just couldn't get to the box in time. But, since then he keeps randomly once every other day pooping on the floor by the front door!! I don't know why because the box gets scooped out once or twice a day, and changed and washed weekly. This last time I caught him in the act and told him no, then brought him to the box and shut the door to the room. I don't know why he's doing this all of a sudden or what to do to stop him. Any input???