If you have some Blair let nes tangled together there, a good idea would be a Y-DNA test on a male Blair from each line. I have always been curious about my grandmother’s Blair line from south Perthshire. It is geographically unlikely that they spring from the Blairs of Blair in Ayrshire. It has yet to be determined if they stem from the Blairs of Bslthayock either. Not being a Blair in the direct male line, I am getting my grandmother’s nephew to donate a Y-DNA sample. That should tell me a few things and should prevent our Blair line from getting tangled the way others have been,