My brother's BigY test recently verified what I and others have believed for a long time: that my James Crawford is somehow related to the James Crawford (1758-1836) of Garrard County, KY that was married to Rebecca Anderson. These results also indicates a relationship to Edward Crawford (1762-1826) of Overton, TN.
One of my yDNA 67 matches is a descendant of William Nelson Crawford (1829-1907). I am also an autosomal DNA match with descendants of William Nelson Crawford. This descendant also shares autosomal DNA with a descendant of James Crawford (1770-1833) who married Martha Knight and with a descendant of William Crawford (1748-1809). James Crawford (1770-1833) and William Crawford (1748-1809) were both in the Garrard County, KY area at the same time as my ancestor.
A descendant of Alexander Crawford (1715-1764) is grouped in the R1b group on the Crawford project.
The researcher who is a descendant of William Crawford (1748-1809) believes that his William Crawford is a 1st cousin once removed from Alexander Crawford.
The above photo is an attempt to show how this researcher believes these various lines might be related. Note that my James Crawford line is not connected. Nor is the Edward Crawford line.