10 wk old female labrador/retriever? I have tried to introduce gradually - jack russell has not taken too kindly to the puppy and I am afraid she will hurt her. I walk both together and they are walking okay - my jack russell will growl and snap at the puppy every now and again, I have not left them alone together though as the jack russell has shown signs of wanting to attack the puppy when we are in our garden at home. Any tips on how best to do this?