I am research the McLean Family who lived in Nelson County Kentucky. My roadblock is William McLain who was my ggg grandfather. He married Mary Aloysia Layton in Nelson County Kentucky in March of 1807. I see his name associated with John McLean and a Arthur McLean, but do not know the association. My William & Mary (Ally) traveled to Perry County Missouri. Anyone with info on William's parents or where he may have come from before Kentucky. I would appreciate any help.