Hi there, I am a descendant of Capt. Nathaniel as well.I made a short to Edgefield a year or so ago, I had the opportunity to meet with the town Historian, a gentleman by the name of Bettis Rainsford. Mr. Rainsford is pretty well informed about the Abney family history. I had the chance to visit the local History library; the Tompkins Library and there was quite a bit of history about the Abneys. In one of the books, i found in the Library was a snippet about the burial site of Nathaniel and his family. According to this book, the tombstones were removed in the 1950's by the D.O.T of South Carolina.As I recall, the site was near a highway and they for some reason or another removed the tombstones. I will try to find my notes and see if I can find the title of the book and some more info for you.