I have two boys, 4 and 2 years, both intact and no intention to neuter. They were only the best of friends until about 6 months ago. First it was over toys, then bones and later seemlesly without a cause. The older boy always starts it, but when attacked the younger will get grazy too.
In my opinion and at least in our house it's a leadership problem. When they know who is the leader, meaning me and my hubby, they don't have to fight, at least not that much. I'm sure there will be minor scuffles, but I have already had great results with training myself.
We did 3 weeks of what is called "ice age". We didn't notice them at all. We gave them their food and of course did normal maintanence. All walks were short and on a leash. We didn't look at them, touch them or talk to them for the first week. You're not supposed to even discipline them if they misbehave and they can start doing so just to get your attention, mine luckily didn't. The second week you can discipline them, but no more attention. The third week you can ask them to come to you and pet for awhile, just for few minutes and then ask them to go away. After this 3 weeks period you still have to practive normal leadership behaviour, meaning for one that you don't give them any attention when they ask for it. You need of course to interact with them, play with them and pet them, but it's when you wan't it. Also you have to treat the older one like he is the top dog from the dogs. Even if there's a fight and the older one starts it you have to first punish the younger one. There is more to it, but if you decide to try you're better of hiring a trainer or at least buying a book about it.
I have had great results. Before the fights were almost daily, but since we've had two minor incidents. They're playing together and sleeping in the same room. The older boy is also more obedient than he use to be. He will stil growl if asked to do something he doesn't want, but he will do it. I'm sure in time he will give up his throne completely...I also need to train myself how to treat them more as dogs, they already know how to be dogs.....good luck.
