Hi Bill, In my amatuerish manner, after looking at the given Newbattle names of your Allan's and mine of the same generation, I suggest that if connected -- the two lines are separated by more than a generation.
Your Allans: (males) David, Thomas, Thomas, Robert, David, David (females) Elizabeth, Margaret, Elizabeth, Agnes, Marion (1727-1815)
My Allans:(Males) Alexander, Alexander, John, William, Robert, James, James(1762 -1817).
Robert is the only double entry.My Robert Allan is the 4th son, therefore probably named after an uncle not a grandfather. (born May 1794, Liberton)
Your Robert is the second son (with some obvious gaps where other children would have been expected to be born), perhaps also named after an uncle. (Born 1773, Newbattle)
A weak link, for sure!!I'll Keep your file just in case I come across some breakthrough with the previous generation. Gratefully, Diane in sunny California