Aggressive Shepherd Cross
We have a German Shepard x that we got from my husband's sister because she didn't want him. He has always been pretty excitable, the last few weeks he has been showing a lot of aggression towards people who go past the house, strangers coming into the house and my son's friends. I generally feed my dog twice per day, mid morning, and late afternoon. If my husband sits near him he growls, he has also started growling at me if I stay near him when he is eating. He has started growling at all of us if he has a bone, but barks aggressively towards my son if he goes within a couple of metres of him.
I am confused on how his behavior has changed. I have taught him to sit shake and fetch, he is now no longer interested in fetch and will only sit and shake for food. I am at a loss, he is not desexed, we are planning to get him done, and people have commented his aggression will calm down when he does get it done but I am unconvinced. Any advice would be helpful.