Ah, adoption! Again it raises its head! Felix G. Shipp and his younger siblings were also adopted by Josiah Shipp around 1815 in Hickman County, TN. His will defines them as "children of Mary McClanahan". My ancestor was the eldest of her children, but NOT adopted, so there is the rub. Who was John McClanahan's father? Could he have been killed during the War of 1812? Was Mary married, or was that her maiden name?

I think the Higgenbotham sisters were daughters of James and Mary Brown Higginbotham of Louisiana. I think they came also from South Carolina. Maybe that info could help your research?
John