Her mother was Annie Geraldine Redmayne and her father was Francis John Tennant of Innes, Morayshire, and Lympne Castle, Kent.
Her paternal grandfather was the industrialist Sir Charles Tennant, 1st Baronet.
Her father, who was a member of The Souls, was the younger brother of Edward Tennant, 1st Baron Glenconner and Margot Asquith, the wife of British Prime Minister H. H.
[2] As a close friend to the Duke and Duchess of York, Manners disliked Wallis Simpson and disapproved of Edward VIII's abdication.
[2] She married John Henry Montague Manners, Marquess of Granby, the son of Henry Manners, 8th Duke of Rutland and Violet Lindsay, on 27 January 1916 at St Margaret's, Westminster.