Diane, I have a bit of information that may or may not be helpful. In my family there is a William McIlwee b.1791 d. 1840 in Frederick Cty. Virginia. He married Margaret Himelright and they had 8 children. One was John H. McElwee b. 1818 Frederick County, VA, d. 1882 Delaware County, Ohio. JohnH. married Catherine A. Orndorff. They had 9 children and one of them was John. Another one of the 9 was Joseph W. b. 1845 d. 1927 and married a Mary Haycook.
It can get confusing as names repeat from generation to generation. I wonder if your John H. could have been a brother to William since their birth dates are close. Do you have anything connection Frederick County VA McElwees/McIlwees to the W. VA group. Good Luck Karen