Thanks so much to all of you who replied. I was hoping that someone would answer in a few weeks!
William F. Jones was indeed the son of Thomas (a Civil War veteran) and Martha Maxwell Jones. He is listed in some earlier censuses as "Freddie." I have lots of information on Martha, as she was the sister of my great grandfather, John Miller Maxwell. I don't know for sure if Thomas and Cassius Jones were related.
My friend and her relatives will be very happy to get this information about the Chavis family.