It seems as if we’re cousins. The James J Cowan you mentioned (your ancestor’s brother) is my 3rd great grandfather. He married Mattie Eckles and had my 2nd great grandfather, James M Cowan, who married Maggie McNeal and had Cornelia Cowan, who was my great grandmother... my maternal grandfathers mother. We have a lot of relations in Mississippi there, in and around Yazoo. I have information on the James M Wall side.