OK. I went to your home page with documents you've posted and I think I've figured it out. The Thomas Ragan (Ragains, etc.) you mentioned -- father of your ancestor Susan or Susanna-is, I believe, the FATHER of the Thomas Ragan I'm trying to learn about who married Keziah Shaw in Davidson Co. in 1812. Susanna would have been his sister. My Thomas Ragan, born 1779, is the first child of Thomas Ragan (born 1753) and Elizabeth Featherkille. He is listed in the first document on your home page as well as the second document.
Thanks for the information. Everybody and his neighbor seems to want to adopt Thomas and Elizabeth for their tree, but you've got a tight line that looks pretty accurate as compared to most of the others. If I can show that Thomas Ragan (1779) is the same one who's in Davidson Co. in 1812 (married there, joined the militia, 1816 tax rolls) I think I can prove he is the father of James H. Ragan, my gg grandfather (1818-1897) who lived his entire life there.