Joan Harmon could help you as much as anyone I know, but I haven't been able to "raise her" now for some time. If anyone who has still been in touch with her please let me know as I am hesitant to quote and send info of her work w/o her knowledge and agreement.
Her "Descendants of John Clatterbuck" sent me some years ago begins with John (ab.1640-abt. 1725) of Bartley, Hampshire. Came to Va in 1660. [Fact 1:]
Her account reflects one child, a Richard(1670-1725). John, above, is my seven G grandfather on the maternal side.