Diane,
Please go to the (free) Cowgill Cousins site at cowgillcousins.org. Your Cowgill connection is there, from Rachel back. As a Cowgill historian, I don't have much on the Kerns other than listing Rachel's marriage to Jacob. My mother, in her Cowgill History book, mentions "For more detailed information on this Kerns family, see Sec 8, Kerns Family, pp 809-844, of Shanholtzer History and Allied Family Roots of Hampshire County, West Virginia, and Frederick County, Virginia, by Wilmer L. Kerns, PhD, published 1980."