How to be sure that inheritance is being divided as stated in will?

My parents have divided their assets evenly among us three kids. My brother who had been unemployed and moved in with my parents ( after he found 1 week earlier I was interested in moving into the home after my parents were gone) but now he remains to live there even tho he is employed , he has more than likely been named executor of the will since he has my parents afraid they can't live without his help...even though everything is split 3 ways, there is so many extra things such as income from rental property, land that is farmed by others and so many other things that he will have control of that we other two don't even know about...do I need to have a lawyer myself to help protect my 1/3...my brother by the way is making it clear that he is in control of things and plans on staying in the home that will be only a 1/3 his...I under no circumstances will sell my 1/3 of anything to him because of the way he is doing. If so, what kind of help should I seek. I am a true believer now, that too much power corrupts as it has surely done him.