[John From PA]

We have had a yorkie for about 4 months now. We got it when it was 9 months old. I have been training it to obey simple instructions such as sit, stay, come, heel, etc. Seems to listen to me very well. My wife and daughter get marginal results but they are getting better. I feel the dog looks to me as more of the leader in the family since I am the one doing most of the training. However, the dog seems very protective of my wife. On several occassions the dog has acted very aggressive towards me and my daughter. This happens when the dog is sitting with my wife on the couch for example and we walk into the room. Particularly if my wife is asleep. Once this happens I am able to tell the dog to sit and he will eventually listen to me. But the intitial aggressive behavior troubles me. It hasn't bitten anyone but I feel that may be next unless I do something to stop this behavior. Any ideas?