She was related by blood or marriage to leading Victorian families; one of her father's sisters married Lord Charles Montagu Douglas Scott, son of the 5th Duke of Buccleuch.

[2] Casey was educated privately, and when she was 14 years old she left Australia to attend St George's Boarding School in Ascot, England.

[6] In Egypt, she was a confidante of wartime leaders Winston Churchill, Field-Marshal Lord Montgomery and Harold Macmillan as well as an indefatigable war worker; in Bengal she fought to raise the status of Indian women, discussed political affairs with Jawaharlal Nehru.

They maintained contact via airmail correspondence and gifts, gave letters of recommendation for international visitors to each other and met up during her visits to the UK.

[2] In 1980, Rare Encounters included the reminiscences of Lady Edwina Mountbatten, Viscount Montgomery of Alamein, Dame Nellie Melba and her mother in law, Evelyn Casey.

She was a member of the International Committee appointed to judge a work of sculpture to honour the "Unknown Political Prisoner", and she had a long association with the Museum of Modern Art in New York City.

On their return to Australia they took flying lessons and once they had earned their licences, bought a yellow Percival Vega Gull aeroplane, and built an airstrip at Edrington, Berwick, near Melbourne, which they had inherited and flew between their homes.

[3] In 1950 she became the first patron of the Australian Women Pilots' Association (AWPA) at its inaugural meeting at Bankstown, New South Wales on 16 September 1950[9] and in October 1953 flew her Miles Messenger plane in Australia's first all-woman air race.

In 1954 Casey became of member of the Ninety-Nines, an American women pilots organisation founded by Amelia Earhart and continued to fly a Cessna well into retirement.

After his retirement as Governor-General of Australia (1965–69), they purchased a house built by Eugene von Guerard in East Melbourne, and her last years were spent in Berwick.

Glittering Surfaces, a detailed biography of Casey, based on extensive archival research and featuring a critical assessment of her personality and achievements and candidly surveying her relations with her children, husband and other colleagues and intimates, was published by Diane Langmore in 1997.