At this point, the oldest known Keller in my line is Christian Keller, born about 1828.  He had a daughter Rebecca B Keller, born June 21, 1853 and died February 14, 1936, who married Isaac B Sensensig, born April 4, 1853 and died May 9, 1926.  Rebecca married Israel B Sensenig and they had my grandmother, Fianna Keller Sensenig, who married Clayton Oberholtzer Martin, my grandparents.