Lady Westbury's career with
St John Ambulance began when she became County Vice-president of the East Riding of Yorkshire in 1954. Her grandfather Lord Scarbrough had been Sub-Prior of the
Order of St John, which oversees the ambulance brigade, from 1923 to 1943. In 1983, with Princess Margaret's encouragement, she accepted the position of superintendent-in-chief. In this role, she modernized and expanded the outreach of the organization. She organized a party in
Hyde Park attended by Queen Elizabeth II to celebrate its centenary in 1988. She stepped down as superintendent-in-chief in 1990 and was made a Dame Grand Cross of the Order of St John, having already been made an Officer in 1975, a Commander in 1980 and a Dame in 1983. She was also made a Commander of the
Order of the British Empire in the
1990 New Year Honours. From 1984, she also served as president of the Women's Electrical Association. She also sat on the grant sub-committee of the
Royal Variety Charity. ==Marriage and family==