I am also a descendant of Emanuel Yahne - he is my 3rd Ggrandfather. Emanuel and Emily's son was Frederick Harrison Yahne. He married Elizabeth Sebring and his daughter was Nora Ellen Yahne. She married Carl Hoover and their daughter was Opal B. Hoover. She married Fred D. Keefer and their son is William G. Keefer. He married Elizabeth McClure and their daughter is me, Kathie Keefer.
I have a lot of information on Emanuel, including a copy of a handwritten letter to his brother during the Civil War. Let me know if you need any information :-)