The first cousin, once removed of the Bachelor Duke, another William Cavendish, would become the 7th Duke of Devonshire in 1858. He married Blanche Howard, daughter of the 6th Earl of Carlisle, in 1829. She died in 1840 at age 28. Her husband spent the rest of his life mourning her. She had given him five children, including Spencer and Louisa.

In the story… He takes seriously ill at his home in Lancashire in December 1854. Louisa leaves London to care for him and Devonshire House is without a chatelaine, an important post in the Mayfair home of the Bachelor Duke who loves to entertain. Diana is visiting there during this Christmas season. At Spencer’s urging, she fills the vacancy – experimentally at first, but then with demonstrated competence.

Blanche's vase at the far end of the Broad Walk in the Chatsworth garden. The 6th Duke mourned her too. She was his favourite niece.