Question: Who is Duke William Of Mecklenburg-Schwerin's mother-in-law?
Sentence (from "Duke William of Mecklenburg-Schwerin"): Willem of Mecklenburg-Schwerin (Ludwigsburg, 5 March 1827 - Heidelberg, 28 July 1879), was the second son of Hereditary Grand Duke Paul Friedrich of Mecklenburg and his wife Princess Alexandrine of Prussia, daughter of Frederick William III.
Relevant evidence: Yes