It's easy to confuse the Rockbridge and Rockingham Gilmores, but courthouse records, marriage bonds, wills, bible records, tombstones and land deeds settle most of our questions. It is well documented that James Gilmore, s/o John and Agness of Kerr's Creek married Martha Dennison. Their son Robert m. Sarah "Sally" Beatty, and they were the parents of the "Gilmore Granddaughters" named in John Beatty's will. In spite of what was often reported, joint efforts by a group of Gilmore/Beatty/Logan researchers a few years ago pretty much proved that John Beatty did NOT have a daughter named Martha.
http://boards.ancestry.com/thread.aspx?mv=flat&m=583&p=localities.northam.usa.states.virginia.counties.rockbridge