I believe the book you are talking about is the republication of Anna Russell des Cognets', Governor Garrard of Kentucky; His Descendants and Relatives. This version was published privately by Mrs des Cognets' grandson, Louis des Cognets, Jr in 1962. In doing so he added his work called, A Postscript About the Garrard Family, in which he treats the relationship between the Garrards and the Lincolns, the Adamses and the Washingtons. If this is not the book, I think all of us would appreciate knowing which one your cousin actually has. Who was the father of John Garrard, your great-grandfather?