Sir Horace Seymour K.C.H. (1791-1851) was the son of Admiral Lord Hugh Seymour and Lady Anne Horatia Waldegrave. His third daughter by his first marriage to Elizabeth Malet Palk, Adelaide Horatia Elizabeth Seymour (1825-1877), married Frederick, 4th Earl Spencer (1798-1857). Sir Horace married second the sister of the 4th Earl's first wife Georgiana Elizabeth Poyntz (1799-1851). For a miniature of him see lot 281.