My father-in-law and one of my daughters are both mumblers. But my father needs hearing aids. Best way to make sure father-in-law speaks up is to have my fath

My father-in-law and one of my daughters are both mumblers. But my father needs hearing aids. Best way to make sure father-in-law speaks up is to have my father around. Downside is it physically wears my father-in-law out. He just can't handle expending that much effort into speaking.