Mary Doublet (c1721-1801) was the daughter of Francis Doublet and Constantia van der Beck. On 29th October 1743, she married Robert Darcy, 4th Earl of Holderness; they had three children, but only Lady Amelia Darcy survived childhood. In a footnote to Carter’s letter to Montagu of 21st June 1768, Montagu Pennington wrote, “This amiable, sensible, and sweet-tempered lady, was a kind and warm friend to Mrs. Carter, from the time of their first acquaintance to the day of her death. The Editor re¬members with particular delight the days which he had the honor to pass in her society, when, after Lord Holdernesse's death, she spent her summers at Deal castle. Her conver¬sation was so full of anecdote, and of knowledge of life, and her manners so agreeable, that it was always a treat to be in her company.”