One of his grandmothers was Mary Elizabeth Schultz 1849-1914. And she was a daughter of William Schultz and Leah Keller. Now we are getting somewhere. Leah was from Dauphin County, PA, a daughter of Michael Keller and Mary 'Polly' Cassel. William Schultz died in 1848 and Leah remarried, to a John Jacob Schaeffer, and had at least two more children, but after that I have lost track of her and do not know exactly when or where she died.
Doctors leave tracks.
I have obituaries of both brothers which you can see by clicking on their names. These cast quite a bit of light on the family, as well as on the 19th century style in obituaries. The deceased was a graduate of Jefferson Medical College in Philadelphia and was actively engaged in the practice of medicine for upwards of 25 years. Several years ago he abandoned his profession owing to ill health, and spent his leisure in the management of his farms which apparently afforded him much recreation. The Doctor was a man of exemplary character and universally respected by all who knew him.