Mother had five brothers, all deceased. They have at least two living sons and at least three living grandsons. I don't know if any of them would be interested in the DNA testing. Unfortunately I am the most active family tree searcher in our Wilcox family. It has fallen on me to do the vast majority of the looking. I will let them know of the Wilcoxson DNA project and let them decide for theirselves.
A couple of years ago I contacted the wife of one of one of my Wilcox/Wilcoxson cousins. This branch of the family kept the full Wilcoxson name. As far as I can figure out, it was my great grandfather Martin VanBuren Wilcox who dropped the 'son' from our family line. I have seen his name spelled both with and without the 'son'.
I did find one very interesting thread in my family line, though not directly Wilcox related. One of my McGuire gxx grandfathers married a Nancy Church. She was the granddaughter of John 'Yenkee' Church. John was a contemporary of Sarah's brother Daniel and they most probably knew each other. They hunted wolf skins as bounties and show up on a bounty pay record in Rowan Couuty, on the same page. It is conceavable that Sarah also knew John Church.
Another interesting twist that shows the closeness of families in Northwestern NC. John 'Yankee' Church is also one of my praternal ancestors. I am a direct descendent of John on both sides of my family. Though I am not my "own grandpa" LOL, I am my own cousin.