Question: What is the date of death of Princess Antonia Of Luxembourg's husband?
Sentence (from "Princess Antonia of Luxembourg"): (Antoinette Roberte Sophie Wilhelmine; 7 October 1899 – 31 July 1954) was a member of the Luxembourgish House of Nassau-Weilburg and the last Crown Princess of Bavaria as the wife of Crown Prince Rupprecht.
Relevant evidence: Yes