i have a 2 yr ol.d english mastiff that i resuced from a neighbor that was neglecting this dog. he is a 2yr old mastiff. his previous owner worked 12 hour days and would come home and leave the dog outside by himself with no attention. my wife and i took with the hope that we could give him a good home with lots of love and attention. he is fine around my wife and i and even our other dog. a mixture of scottish terrier and aussie, also a resuce. but when other people come around he turns into another dog. just last night he tried to come through the sliding glkass door after my brother. and he nipped at my mom. i want to try and help him but i dont want someone bitten. the shelters by me wont help because of the aggressiveness and the rescue organization out here in southern california has yet to get back to me. he is not neutered. would that remove some of the aggression? help!