Thank you for your response and apologies for my delayed reply. I am interested in figuring this out. I am aware of the Becky Cotton story but haven't found a smoking gun proving Stephen is Becky's brother. I'd love to know if you have documentation or even family legend.
My family lore is this: two Kennedy brothers married two Ellis sisters. I can't find where your Stephen had a brother. We believe the brother to be Jesse who married Mary Elizabeth Ellis, Patsy's sister. I just can't document the Stephen & Jesse and Patsy & Mary Elizabeth sibling ties.
My great grandmother believed she was cousins with Julia Blocker, Stephen Kennedy's granddaughter thru his daughter Elizabeth Ann. Both families carried similar stories of ancestors as found in both their obits, stories about descendancy from the Ellises of Va and Amenettes of France. It's those obits and the oral tradition that keeps me believing that Stephen had a brother who was my 3 ggf, Jesse Kennedy.
I'm headed shortly on a research trip to Avoyelles Parish, La. where Jesse & Mary Elizabeth settled after leaving Natchez. I found nothing at the archives at Jackson last year. I'd be happy to hear any theories/recommendations you may. -Eleanor