Hi there. My dog is 3/4 pyr, 1/8 newfie, and 1/8 st bernard. She is 7 months old. She can get really aggressive towards people who come in the house. Just today my friend had a friend over and she got along with him pretty well. I had them meet outside of the house. She let him pet her and she seemed pretty okay. Then later he tried to come in the house and she barked at him. Luckily he is really understanding and he sat down with her and took his hat off and she calmed right down loved his pets and leaned her head into him like she would with me. Then we all got up and he walked farther into the house and she just lost it. She chased after him and barked. She has given people a little nip on the pants before, but she's never actually bitten anyone with force. However, I don't trust her around strangers and I'm unsure of how to work with her. I feel like when I hold her back it puts her on edge and if feels like it escalates the situation. As of right now I hold her back and make her go lay down, but she just watches the person in the house the whole time.

Some background info - she loves the people she met as a puppy. She has never showed signs of aggression towards the people she knows and I take away her food, treats, toys, bones and she has no problem at all. She doesn't really like strangers even in public spaces, but she mostly ignores people. She loves meeting new dogs and also seems to not clue in to dog social cues when they don't want to play.

Any help, thoughts, or opinions are greatly appreciated!!

Oh also I got her because my last dog was 1/2 pyr and 1/2 malamute and she was just a gem. I wanted to get a pyr because we have some dwarf goats I thought she would love to watch them. Unfortunately she ran into the electric fence when the goats we in the fence and now she thinks they're electric...and still hasn't figured out the electric fence.