A friend of mine has recently adopted a 2 year old female pitty from my shelter. She came in stray but I do have a limited history on her. Basicly nice dog, no training, breeder.... She has turned out to be a wonderful pet for them, but now that a couple of weeks have passed and she's settled into her new home she is guarding my friend from anyone outside the house. I've dealt with this in sheppards and Rotts but havn't ever seen it in a pitbull. The neighborhood that they live in is busy and they don't want her grabbing anyone if they get too close. What's the best way to get rid of this??