Question: Who is Mary Montagu Douglas Scott, Duchess Of Buccleuch's father-in-law?
Sentence (from "Mary Montagu Douglas Scott, Duchess of Buccleuch"): On 21 April 1921 she married Walter Montagu Douglas Scott, 8th Duke of Buccleuch and 10th Duke of Queensberry; she was styled "Duchess of Buccleuch" from 19 October 1935.
Relevant evidence: Yes