Hi, just wondering...My girlfriend recently added a female chihuahua puppy (9 weeks old) to her household with a 8 year old male dachshund who has been the "only" dog. He seems very eager to be near her and whines when we don't allow him to get close to her in fear of an attack. He seems to smother her and she growls. Were not sure what are his intentions, we let them interact one time freely for a couple seconds. Were not sure what happen but as a result, she came running to me yepling. His hair is not sticking up or anything, his tail is wagging liky crazy. Were afraid that he might think that she is like a rodent or something so he might attack. What would be the best way for them to begin to get along?