Greetings. I have an issue I hope you can help me with. I have 3 male dogs. 5 yo lab/shepherd, 2 yo lab/pit & the most recent addition a 11+ mo bouvie/poodle mix. All the dogs are neutered and get along great......until recently. My bouvie has started to aggressively attack my lab/pit mix Milo. Milo is the sweetest most gentle dog, and does not "fight" back. We have had the bouvie since March (got him from a reputable breeder when he was 16 wks). We just recently had the bouvie neutered as we noticed some aggression, but only with Milo. The breeder suggested we wait until he was 18 mo so he would receive all his growth hormones, he currently weights 82 lbs. I am guessing this is a pack dominance behavior but have to say I do not care for it. We do not use harmful training technics and the dogs are never hit. How do I stop this behavior before one of my dogs gets hurt? We do not have professional training centers in the small town I live in, the best we have is agility training. We have a large fenced in yard and all the dogs have plenty of exercise daily. Also the aggression only happens when the dogs are in the house. They play just fine outside.