Georgiana Cavendish was a sister of the 6th Duke of Devonshire. She married George Howard who became the 6th Earl of Carlisle and the owner of Castle Howard. He died in 1848 and their son, George, became the 7th Earl. He never married. He had a sister, Blanche, who married the future 7th Duke of Devonshire. They had four children who survived childhood, including Spencer and Louisa Cavendish. The siblings liked to travel each year visiting Cavendish properties and relatives.

In the story... Spencer and Louisa invite Diana to join them on their annual ramble. Their first stop is Castle Howard where they spend a few days with Grandma Howard.