If a person is in clear mind they can elect anyone to be their Power of Attorney as long at the person elected will accept said position.
Example, my sig other is my Power of Attorney, and if something happen to him and he cannot serve as my POA, then my Elder Law Attorney has been assigned to be the back-up POA.
Example, my sig other is my Power of Attorney, and if something happen to him and he cannot serve as my POA, then my Elder Law Attorney has been assigned to be the back-up POA.