need some advice...as some of you know, I lost my Lab over Thanksgiving. I rescued a Yorkie Mix puppy 6 weeks ago & my older dog that I still have wants nothing to do with him which is understandable. The rescue contacted me about my new pup's sister still being in foster care and asked if I would take her too. I picked her up last night and brought her home - my first rescue being a male dog of course tried to assert his dominance, which she allowed at first, however, today she seems to be just as assertive back. I figured being siblings they would get along. The do play alot and sleep on my lap together but they do have a few "fights", teeth showing, growling, etc. I have starting intervening, yelling loudly to settle down and putting the boy in a crate for a few minutes, somewhat of a puppy time out and that seems to help for a while. Is there something I should or should not be doing? My vet said this will subside in a few days but I just don't want either one getting hurt. They were only separated for 6 weeks. They are 14 weeks old and per my vet, will not get Spayed/Neutered for one more month. Since I'm not familiar with Yorkies, I don't know if this behavior is breed related or just their normal behavior. It's been 8 yrs since I've had puppies in the house...