Question: Who is the maternal grandfather of Prince Frederick Of Hohenzollern-Sigmaringen?
Sentence (from "Karl Anton, Prince of Hohenzollern"): Prince Karl Anton of Hohenzollern- Sigmaringen( 7 September 1811 – 2 June 1885) was head of the Princely House of Hohenzollern- Sigmaringen, Hohenzollern from 1869 and Prime Minister of Prussia.
Relevant evidence: No