Last name is spelled incorrectly on 1880 census...sorry that I left that out! They are listed as family 234, dwelling 235, William Schrader, in Township 3 South Range 6 West. I don't have DOB for either William or Lena, but based on rest of family William is either Osterkappeln or Osnabruck, Niedersachsen, Hannover.
The Feger family also on same page is most likely Lena's sister in law since Feger is her maiden name. As this lady is listed as a widow, I surmise that William & Lena moved there to help w/farm after husband died. (Husband is on 1870 census, the Schroeder family on following page is not ours).
Are you in Marissa area?