The Elizabeth Follis of Giles, TN 1850 census was born about 1803. This would make it very improbable that she married Jacob Follis in 1779.She is more likely Elizabeth Martin,the wd of John Follis, and who moved to Montgomery Co, IL. Her son Henry Clay Follis lists John Follis as his father on his marriage record. Henry Clay was born in 1844 and Elizabeth Young would have been in her 80's at that time. I believe the children you have listed are the children of John and Elizabeth Martin Follis. On the 1850 Giles census the W.D. Myers family is close by the Elizabeth Follis family. Next door to W. D. Myers is their son John Myers and wife Mary M. Follis Myers and Mary's brother Abram. Next door to them is William R. Follis and Eliza Myers who were married in Giles 14 Nov 1849. Robert Martin Follis is also living close by with another family learning the blacksmith trade. In the biography of Robert Follis it states that John and Elizabeth Martin Follis had11 children. If you add Robert, Mary,Abraham, and William R. to the seven listed with Elizabeth Follis in 1850 there would be 11 children.