A scuffle can come from nowhere and happen in a second. At ten weeks, they will begin to show signs of hormonal behavior soon if they don't already and fighting will come with it, so stevesmum's suggestion is a very valid one. I trust you are aware that your rabbits have to be neutered and that you can't let intact rabbits which aren't babies anymore live together? Two males is a tricky and very risky combination, the fact that they are brothers don't play into this equation at all. Even neutered there is no guarantee they will be able to live together peacefully as adults. Maybe they will, if you are lucky. But you have to separate them now until they are neutered anyway because even if they aren't fighting now, they will be (there is no question about it) when the hormones will kick in. You won't necessarily be there to stop it when it will and your rabbits could very seriously hurt each other (ever saw rabbits humping each other from the wrong end to assess dominance? Well, if the guy underneath doesn't like it, he might be tempted to bite where it really hurt and that's one neuter without anesthesia for 'would be king').
