Looking for something (marriage cert's, death cert's, or Obit's) to give parents of the following family of siblings. These four have been confirmed as siblings though Ernest August Pontow's obituary:
1) Henrietta Pontow b.1838(GR) m.(1858, Mills, IA) Charles A. Donner
2) Ernest August Pontow b.5 Sept 1841 Schonlake, Germany; d.27 Dec 1916 Mills, IA; m.(1868, Mills, IA) Henrietta Josephine Warnke.
3) Wilhelmina Pontow b.23 July 1939 Schonlanke; d. 20 Dec 1919 Malvern, Mills, IA; m.(30 Nov 1860, Marshall, IL) Frederick Zanders
4) "Mrs. Amelie Zanders" Likely Amalie Pontow b.1846 d. 28 Dec 1899 Mills, IA; m1. Fred Donner; m2.(29 Feb 1880) William Zanders.

Also very curious on parents of
William Zanders who died 22 Apr 1904, Mills, IA.
and
Frederick Zanders (1837-1917)

Thanks in advance for research help from anyone!
Torrey
copferfam@gmail.com