 His former friend, John Sackville, 3rd Duke of Dorset, had died in July 1799, and on 7 April 1801 he married the widow Duchess Arabella Diana (daughter of Sir Charles Cope, Bt., by Catharine, fifth daughter of Cecil Bisshop, bart., of Parham, who afterwards married Lord Liverpool).She was a capable woman of thirty-two, with a taste for power and pleasure, says Wraxall, kept ""always subordinate to her economy"".By the death of the Duke she came into possession of £13,000 a year, besides the borough of East Grinstead, while Dorset House and Knole Park subsequently passed into her hands.