A friend of mine recently moved into a home in the countryside area near Sterling Virginia. His home backs up to a very thick wooded area. While recently exploring in the woods with his kids, he discovered a small abandoned cemetery comprised of Jenkins family members that dates to the 1800s. He seems to recall that one of the graves was for a Jemima Jenkins, and the last grave in the plot dates to 1937.
You may Already be aware of its location, but I am happy to make the connection if it is indeed related to your family.