Contest Power of Attorney My brother has power of attorney over my 87 yr.

Contest Power of Attorney
My brother has power of attorney over my 87 yr. old. mother. He is very ill and could die at any time from liver and kidney failure. He informed me he has set up a trust of my mother’s assets with our 22 yr old caretaker of four months in complete control of my mother’s care including health decisions. He is a chronic alcoholic and paranoid at this point. What is my recourse. He has lived with my mother for 15 years with no employment other than being her caretaker. What is my recourse?