Sorry so long to reply - computer problems about three weeks ago have kept me offline until today.
William Nathan Kimbell's wife was Lucy Ann (Lula) Carter. They were married June 28, 1905. He had several brothers (names unknown) and a sister named Sally. He had two daughters, Helen Carter Kimbell (my grandmother) and Mary Kimbell.
I am intrigued by your Tishomingo County, Mississippi discovery. It could very well be him. As she was 10 when he died, my grandmother knows very few details of her father's life. I have never heard anything of the Stewart family, but will ask my grandmother soon.
Thank you for replying to my post! If you find anything else I will be greatly appreciative.