I found them living with a sister-in-law. Name was spelled different too.
living at 9 Locust St., Lancaster, PA 1900 - 1920
Harry Ehrhart b. Sep 1852
Mary E.(Acker) b. Mar 1849
Mary E. Ehrhart b. Apr 1884
William H. Ehrhart b. APr 1886
If you are part of this family, I would still like to hear from you.
Tina