If you have a comprehensive estate plan, you will have powers of attorney in place in the event you can no longer make decisions for yourself. However, just because there is a plan in place, it doesn't mean everything will go smoothly.
In a large estate, with few inheritors, what happens when there are serious allegations about elder abuse levied at the beneficiary? This exact situation is playing out, in the recently revealed details of a pop culture legend's dealings with his only daughter.
There has never been a plan that has perfectly withstood the act of implementation. That includes estate plans. Because of that simple fact, it is vital that you select an executor who will minimize the possibility of a lawsuit.