Lord Frederick Cavendish British politician and field marshal (1729-1803) (1729–1803) Parents Catherine Cavendish, Duchess of Devonshire William Cavendish, 3rd Duke of Devonshire Children Siblings Lord John Cavendish Lady Rachel Cavendish William Cavendish, 4th Duke of Devonshire Lady Caroline Cavendish Lady Elizabeth Cavendish Lord George Cavendish