I am Christian Fahrner's great-great grandson. One of his children was Charles Ferdinand Fahrner (known as Ferd), born around 1880. He had five or six children, three of whom survived childhood. These were Lillian, Edward and H Raymond. I am Edward's son.
Family lore was that Christian was a shoe maker, and that he made the boots for Gen. Sheridan of the Civil War. I have no reason to doubt this - there were old shoe lasts lying around the basement.
Somewhere in the family are Christian's naturalization papers. I'll contact my cousin and see if Eva's maiden name is on the form.
Your ggm is my grandfather's sister, so the Dougherty's children are my dad's cousins. I believe I met a number of them at my father's funeral in 1983. Ferd, if you care, was a candymaker by trade, though he also worked in manufacturing.
Regarding "country" of origin, they were from near Baden-Baden, in the Black Forest. (Germany was not unified until 1871.) If you look in the German on-line phonebooks, you will see that Baiersbronn is still a Fahrner hotbed, and looks like the root source of the family.
PS I believe that Christian died in 1901.