Most of our McLins seemed to have dark hair and gray eyes. They seemed to be of smaller stature, 5'10 or so, and thin, except for my great grandma Margaret--she appears to have been a big heavy girl and her daughter was rather big and heavy. They must have been good cooks. A different line of Maclins of Pennsylvania appear often in census returns and I traced some of them, but they appear to be of German ancestry rather than the Scotch/Irish ancestry of our lines. If your Maclins tend to blue eyes and brown/blond hair they are probably of these lines. That Thomas McClain and Martha Swan might be possibilities, being born of the same time period as my unknown McLin. Since your George named one of his daughters Martha, perhaps that was after his wife.