I second everything MON said - the first paragraph especially!
I will also add - I suspect you'll find that as your boys get older they will (on their own) find interests and passions that will allow them to be involved in separate activities, and worries over competing in extracurriculars will most likely fade into the background. Note - my kids still compete with each other over crazy-silly stuff, but as they've grown they've each found their own sports, their own academic strengths and their own "fun" activities.
If competition in one specific activity is a huge problem at the moment, I'd consider just dropping that activity all together and finding other fun things to do as a family.
Best wishes,
polarbear
