Question: Who is the father-in-law of Countess Xenia Czernichev-Besobrasov?
Sentence (from "Countess Xenia Czernichev-Besobrasov"): Paris20 September 1968, Casteau, Belgium) was the first wife of Archduke Rudolf of Austria, the youngest son of the last reigning Emperor of Austria-Hungary, Charles I.
Relevant evidence: Yes