Thanks for the info. I went to the LSU Special Collections website and found Richard Ellis in the Natchez collection. Unfortunately, his daughter, Mary, wasn't married to a Kennedy. And no mention of another daughter, Elizabeth Ann "Patsy". If you're aware of these women in another context, please do let me know.
The family lore is our Ellis was from a prominent Va. family and descended from Powhatan which would point to Powhatan Ellis but he had only one child.
Mary Elizabeth may be connected to either of these families but I've not found the link.