sentences:  He was the eldest son of Archibald Acheson, 4th Earl of Gosford and Lady Louisa Montagu (1854–1944), a Lady-in-Waiting to Queen Alexandra.His paternal grandparents were Archibald Acheson, 3rd Earl of Gosford and the former Lady Theodosia Brabazon (only daughter of John Brabazon, 10th Earl of Meath).His maternal grandparents were William Montagu, 7th Duke of Manchester and the former Countess Louisa von Alten (a daughter of ).