Aggressive 5 month old mix (pit/golden retriever/ Chesapeake bay retriever) aggressive
We adopted a female pit/retriever mix in January, she was almost 12 weeks old. We always wanted to have 2 dogs in our home. Last weekend we introduced her to a possible sister, the meeting was going ok until the other dog lundged at our girl and bit her neck (she is fine, I am a nurse and checked for wounds) ( btw my girl is not spayed yet, she gets it done on april 5th) anyway... we already had another adoption application in for a new puppy before last week happened. Well we brought our new 8 week old male lab mix home yesterday. My girl is being very dominate towards him and a little aggressive (she keeps nipping him) as soon as we can see her get tense we separate them but I'm worried about our situation. I'm scared that the incident that happened last weekend is causing her to act this way. I know it hasn't even been 24 hours but I want to be able to keep both dogs so I want to try to get this under control before it gets worse. Any advice would be greatly appreciated.