My family tree lists a John Duncan Jr. (Rev. War) married to a Lydia Spiller. Their son, Benjamin S. Duncan, is my ggggrandfather. He married someone with the last name of Trull. Their daughter, Polly Ann Duncan is my gggrandmother. She died in Williamson Co., IL. Their seems to be a lot of overlapping names in our trees. In fact, I have another ggggrandmother, Nancy Trull, who married Ephraim Cannon. Their son, William, was married to Polly Ann Duncan, and also married a Cynthia Duncan Vaughn.