Hi Mike, That is my Yarbrough line - I descend from Thomas Yarbrough (b. 1685 VA) through his son, Zachariah, brother to your John(3).I do have proof that John is the son of Richard Y.
1704 20 May.Deed from John Yarbrough to William Aylett.200 acres ...part of great quantity of land formerly leased sold or exchanged by Chickahomney Indians with Arnold, by Arnold conveyed to John Hurt by deed acknowledged in King & Queen County Court 12 Nov 1692; by Hurt sold unto Richard Yarbrough, father of the said John Yarbrough, by deed acknowledged in court records for King & Queen County 12 Feb 1695/6 and is now in possession of John Yarbrough one half by virtue of a deed from his brother Richard Yarbrough and the other half as heir to his the said John Yarbrough's said father. King William Co. VA Deed Book 1, p. 170.
For me, the weak link in the chain has been John being the father of Thomas.There are a couple of Caroline County Virginia court records involving a John Y being a security for Thomas Y. and vice versa.Thomas Y's son John would have been only about 5 years of age when these court hearings took place, which seems to indicate there is a close relationship between John and Thomas -- but this is only circumstantial --- have you found positive proof?If so, pleae share. Karen