Six weeks ago I adopted my yellow lab, Wyatt. Everything has been going great, and he is doing extremely well with housetraining at home. The only concern I have is when he is at my sister’s house. He goes there during the day while I’m at work. They also have a yellow lab. When he is there, Wyatt frequently urinates on the floor while walking, leaving a zigzag trail. He has never done this at home. The only accidents he has had at home are true accidents when we don’t make it to the door in time. Any ideas about why he only does this at my sister’s house and what we can do about it? Thank you!