There were two Nathaniel Abneys in same generation...I take it you are looking for either the Dr.Nathaniel Abney son of Abraham Abney married to Cassandra who had the wife Lucy or are you looking for the Capt.Nathaniel married Isabella Madison who was son of George m. Unity????? The book for Abney Reference is located at DAR Library and also a copy at CDXVIIC Library in Wash. D.C. or you may obtain a copy from Abney Brewer the writer published in 2008....at her email: AbneyBrewer@comcast.netor from her at 1422 East Brooklake Dr. Houston, Texas 77077
There has been much confusion about these Nathaniels...one was son of Abraham m. Cassandra but one was also a son of George m. Unity brother to Abraham....so two Nathaniels in the same generation but Capt was married to Isabella Madison and was son of George m. Unity and had brothers Michael, Samuel, Dannett, William and sister Dorcas.
Good luck with all of this but make sure you have the correct Nathaniel.Thanks for writing...Betty Mayer MAYERBJC@aol.com