Since Bobby is 7 years older than Joey, I also told Joey he could hit his brother. Bobby is an instigator, too. He needles Joey until he either gets furious and throws things at Bobby or bursts into tears only to be told what a "baby" he is.
I have threatened to crack their heads together more than once. At least they have learned to take off their eyeglasses before they start wrestling.
LOL - my boys don't wear glasses, yet. Billy (2-1/2 years older) is taller, and Tom is heavier, so they're evenly matched. I figure we'll get identical results in about 5 years with Patrick and James.