Question: Who is Frederick Of Hohenau's paternal grandfather?
Sentence (from "Frederick of Hohenau"): Frederick, also known as Fritz, was a son of Prince Albrecht of Prussia (1809–1872), who was a brother of Emperor William I and King Frederick William IV of Prussia, from his second, morganatic marriage with Rosalie (1820–1879), daughter of the Prussian War Minister Gustav von Rauch.
Relevant evidence: Yes