Hi I have a 2 year old jack Russell x maltese, she's always been well behaved and clever.
She loved playing with other dogs so when I moved in with my partner he got a puppy, he's a staffy x kelpie. At first they loved eachother and were so cuddly and friendly, only recently she's been starting to be a bit aggressive towards him, nipping and growling at him when we play catch and she bit him on the nose cause he stepped on her while she was asleep and he drew blood.
I'm just getting worried it might become more aggressive when he gets bigger than her. Any suggestions on how to train his out of her? Im not willing to give either of them up and I just need to know if I should be worried about her getting worse. Thanks