My great grandmother Lena Maude Potterfield could possibly have been a daughter..as the dates are in sync. Do you have any records of Luther having any children? Lena married a George W. Morin, around 1910. George, from what I understand was from a family of "railroad-bums". They built a home in nearby Fairplay, Maryland, in Washington County, not too far from the railroad. Which I think connects with the line that runs through Brunswick, Maryland, just across the river. How close is your farm to the Potomac? I understand that Lena also had some Indian blood in her. I have access to several photos of her and my great grandfather George Morin.
Unfortunately, my grandmother never spoke very highly of him.