Boxer Aggression

Question
QUESTION: I have a 2 yr. old female boxer( Millie )she is large @ 80 lbs. She is very playful and energetic recently my sisters lab comes to our house and Millie starts to fight with him he is a very passive older dog and does not start anything he just tries to defend himself. They used to play together and she would get rough with him and he would go back to his house but now she is getting him down and seriously fighting. I do not know why she is doing this now. She has a very dominating personality. Any suggestions why this is happening now? Thanks

ANSWER: It's hard to say without seeing the activity between them, but if your sister's dog just showed up on your Boxer's doorstep after a long absence, without being introduced on neutral territory, and it has been some time since they played, she may just be asserting her "adulthood" and considering him to be an intruder. Or, she may be asserting her position as a more dominant dog.  If the dogs don't get along any more, don't continue to subject your sister's dog to being bullied and pinned.  


---------- FOLLOW-UP ----------

QUESTION: Also my 3 yr. grandson was there , my husband said the lab was getting close to my grandson. he and Millie are inseperable when they are together so I also wonder if that could have been a part of the problem. There was one other time when she got a little rough with lab and my grandson was there also...

Answer
That's an important piece of information.  Some dogs will be protective, or they will guard a human as a "possession", or resource.  Dogs of Millie's age are more likely to assert themselves in these ways.  But, to be on the safe side, it might be a good idea to at least take Millie for a refresher training course so that she has a good "leave it" and "come" and you can redirect her when necessary.  If you cannot be sure that she will respond, don't take a chance of having dog fights occur within an area where a child is present.