You are indeed related to Quanah Parker. My father was a great genealogist and compiled volumnious information on all of the Duty lines from the original 4 brothers that came to America. Cynthia Ann Parker was the daughter of Lucinda Duty, who was the daughter of Richard Duty. Richard was one of the 4 brothers. Cynthia Ann Parker married Peta Wanderer Necona. Their son was Quanah Parker who became a great Comanche Indian Chief.