Question: Who is the maternal grandfather of Prince Friedrich Karl Of Prussia (1828–1885)?
Sentence (from "Princess Marie of Saxe-Weimar-Eisenach (1808–1877)"): Princess Marie of Saxe-Weimar-Eisenach (3 February 1808 in Weimar – 18 January 1877 in Berlin) was a princess of Saxe-Weimar-Eisenach, by birth, and, by marriage, a princess of Prussia.
Relevant evidence: No