I realized after reading your comments on our last post that I needed to give you more information. So here is what led up to the bite and what we did afterwards.
Higgins sleeps in his crate in the kitchen. It is open so he can get out if he wishes, but he cannot get out of the kitchen. We decided he was trustworthy enough to sleep with us so we let him stay on our bed when we went to sleep. He didn't stay long but returned off and on during the night - usually with kisses to our faces. The second night of this routine is when we had the bite incident. Higgins had jumped on the bed and started his "kissing" about 2:30 am. We both told him firmly to knock it off and lie down. As soon as he obeyed, my husband reached down to pat him and say "good boy" - Wham! Higgins bit him. Needless to say the lights came on and we were wide awake. My husband was furious and picked up Higgins by the scruff of his neck and carried him like that down the hall to the kitchen. I'm pretty sure he yelled at him too but I don't remember. He didn't strike him (although I'm sure he wanted too!). We have always tried to train our dogs using positive methods. Hitting isn't positive, but I realize sometimes a dog might deserve a swat. Carrying a dog by the scruff of their neck isn't too positive either, I know...
Anyway, back to the story....
The next morning I got up and went to the kitchen as usual and when I started to open the gate and say "good morning" Higgins started growling at me. I knew if I tried to push it he would bite me. I was certain of it. So I ignored him and let the other dogs in the kitchen so everyone could go outside. He did not growl at me again that day, but he would not come near me. The next two mornings were a repeat of the first morning. He would play ball with me but I had to really work to get him to bring the ball close enough for me to reach it. During this time he never growled at my husband, although he acted reserved with him also. He continued to play with Emma as if nothing had happened.
On the fourth morning he seemed almost normal. It was almost as if he was tired of being ignored while the other dogs got "good morning loves". I am just sure all of this has to do with his sleeping arrangements. But I can't figure out why. In the meantime, he is back to sleeping in the kitchen. Maybe he feels safer in that confined space. His part of the kitchen is about 10'x10'. I have also "upped" his exercise time. A tired dog is a good dog, right?
The comments we got about NILIF and reinforcing his obedience commands are really helpful. We are going to work on these things right away. Higgins has been through twice the amount of obedience classes that most dogs go through. And his sessions were private, one-on-one with the trainer because he does not like other dogs. In that controlled environment we could introduce strange dogs. He still doesn't like strange dogs, but he is much better now at ignoring them.
One last thing. Higgins is due for a Vet visit soon and I will talk to them about this. Of course if needed I will get him in sooner (if we have anymore problems with behaviour).
Thank you all so much for your thoughts, concern, and encouragement!