We just got a dog (boxer/lab mix, male) about 2 months ago for our family, he is almost 2 years old. I have 3 children (9,7, and 2) and he does exceptionally very well with all of us. He is housebroken, very easily trainable, not food aggressive - the issue we have run into is that the dog can be very people aggressive when I am around ( and only with people that are outside of the family). We have noticed this 2-3 times over the last couple weeks. Case in point - tonight my wife was out shopping w/ a friend and her friend's son stayed home w/ me and my 3 kids for a few hours. The dog constantly growled and barked at him, even nipped in the behind. As soon as my wife returned home, he acted like he loved the boy - licked him, played w/ him, etc etc. Any suggestions? We really love the dog and the last thing we want to do is re-home him...just need some direction is changing this behavior. I have done quite a bit of research, but haven't come across anything that really matches this situation. He is not possessive of me or the least bit aggressive any other time.