What are my options for my dog?

Your dog might view your brother as the leader if thats when he calmed down or maybe the dad if thats who he is close to. An YES, obedience training WILL help. Get a trainer( if you can afford), try to see if he acts up when you get close to either your brother or your dad. If he does , then may be trying to protect them. As for how to fix it ....thats up to a trainer