I think I got a likely candidate for your Anne Cannon. I have an Anna M. Cannon b. ca 1858 she was from Horry County, SC the daughter of George and Rebecca Smart Cannon. This Anna M. Cannon had at least two other sisters that died young after being married and having children.... maybe something they had in common. Also this Anna M. Cannon had a brother Benjamin Walker Cannon who named a daughter Maybelle in 1891. I'm thinking that Anna M. Cannon maybe actually be Anna Maybelle Cannon and her daughter Anna Maybelle Skipper was named for her and maybe she died in childbirth?