Question: When was Princess Margaret Of Prussia's husband born?
Sentence (from "Prince Frederick Charles of Hesse"): Frederick Charles Louis Constantine, Prince and Landgrave of Hesse (1 May 1868 – 28 May 1940), "Friedrich Karl Ludwig Konstantin Prinz und Landgraf von Hessen-Kassel" in German, was the brother-in-law of the German Emperor Wilhelm II.
Relevant evidence: Yes