Mary Montagu Douglas Scott, Duchess of Buccleuch Scottish noblewoman (1900-1993) (1900–1993) Parents William Lascelles Sybil Beauclerk Children Elizabeth Percy, Duchess of Northumberland Caroline Montagu Douglas Scott John Scott, 9th Duke of Buccleuch Siblings Diana Lascelles Partners Walter Montagu Douglas Scott, 8th Duke of Buccleuch