Sir Frederick succeeded his brother John Charles as Earl in 1845. He was a Knight of the Order of the Garter, a Knight of St. Louis, of St. Anne of Russia and of the Redeemer of Greece, and was a Companion of the Order of Bath. He seved as a Rear-Admiral, as Lord Chamberlain from 1846-48, and as Lord Steward of hte Household from 1854-57. In 1830 he married Elizabeth Georgina [d. 1851], daughter and co-heiress of William Stephen Poyntz of Sussex (a Member of Parliament). They had a son (John Poyntz, who succeeded his father as 5th Earl), and two daughters. He married secondly to Adelaide Horatia Elizabeth Seymour [d. 1877] in 1854, with whom he had two more children. Daughter Victoria Alexandrina (for whom H.M. Queen Victoria was sponsor) married the 1st Viscount Sandhurst. Son Charles Robert succeeded his half-brother, John Poyntz, as 6th Earl.
Cooper, Douglas, ed. Great Family Collections. New York, 1965:197-240