I noticed your postings on the Genealogy.com message boards. I am descended from some of the same families in Mathews County, VA. You can view my family tree website at http://www.burroughsfamily.com/genealogy.htmlhttp://www.burroughsfamily.com/genealogy.html .
As for Cathron/Catherine Gwathmey, I believe that she is descended from one of three brothers - Richard, John or Owen Gwathmey, of Abingdon Parish, Gloucester County, VA. These three men were sons of the man who seems to be the original Gwathmey immigrant to Gloucester from Wales, Owen Gwathmey/Gwalchmai. Please consider the following quote from my notes:
This is the immigrant Gwathmey who came from Wales. Owen is also a Welsh name.
A letter from John H. Gwathmey to Housey dated 3/5/1938 says "Gwathmey is an old and distinguished name in Virginia. They were large landowners and people of culture. . . Owen was the first of the name in Virginia . . . he settled in Gloucester County. The very fact that so little is known of him, except that he married a widow Arnold--maiden name unknown--makes it appear that he was not anxious for his whereabouts to be advertised."
The letter continues, "The name in Wales was, and still is, Gwalchmai, pronounced very much as we pronouce it today. The Clan Gwalchmai was never conquered by the English, the indication being that Owen Gwathmey fled from Wales, for the reason that he would never recognize an English Prince of Wales. If you will look in the Encycopedia Britannica under "The Celtic Poets" you will find quite a lot about the Gwalchmais, who seem to have produced several noted bards."
Although John Gwathmey twice insists that Owen Gwathmey the immigrant married "the widow Arnold", the book entitled "Ancestral Records and Portraits, Vol 1", copied by Kittie B. Randall, says he married "the widow Cleverins". Reference to the widow Cleverins is made in one other spot.
Owen Gwathmey was on the Quit Rent Roll for Gloucester County in 1704 and a slave of his was baptised at Abingdon Parish in 1714.
As for the Armistead family, I descend from the Armistead line several times. I have had difficulty tying in one ancestor, however. She was called "Suky" Armistead, and she married William K. Burroughs, probably around 1810. She would have been born around 1790. She had sons named William Burroughs, Armistead Burroughs, Warner Burroughs, and a daughter named Susanna Burroughs (probably Suky's real name). I suspect that she was one of the New Point Armisteads, as the Burroughs' lived in New Point and everyone seemed to marry very local there. Anything that you might have on her line would be greatly appreciated.