Oh, my! Angela...I am so sorry, this is such a nightmare! I can't imagine how terrified you must have been.
I understand what happened, I believe, but you never know for sure...generally puppies like to play rough with their littermates, and when we are on their level (even adults sitting on the floor) they go nuts thinking you are there as a littermate and they want to play...only their play at this age is much too rough and once you are down, you can't get back up. It is a very dangerous thing.
Again, generally, it is the dog being playful...but there is always the possibility and the genuine fear that Cody Bear has an aggression trait...and if so, he does need specialized training. It is truly unfortunate that you don't have trainers conveniently available to you.
Our dogs attended what we jokingly called "boot camp" but I wonder if there is a similar program near enough to you that you might be able to place them...we signed up for a week and they worked wonders with the dogs! Of course, you have to continue to work with them, but the foundation is there and they will work on specific problems.
I hate to even suggest this, but you might want to consider a muzzle for Cody Bear when you are not able to be with him and the children.
I just don't have any answers...only possible suggestions. Sometimes professional trainers take the dog to their home and train them for you. This might be the only option you have.
I am terribly sorry that you are facing this horrific decision and that your dear children are placed in this situation...and that Cody Bear is not understanding his place in the pack right now...I hope it will work out well for all of you, but of course...the safety of your children must come first.
I made a quick check on this link:
http://www.veterinarypartner.com
This information was interesting to me...there is a possible connection to sudden changes in behavior (for the dog) and possible physical problems:
http://www.veterinarypartner.com/Conten ... C=0&A=1737