Born: September 2, 1918;

Died: November 22, 2022.

DAME Frances Campbell-Preston DCVO, who has died aged 104, was one of the longest-serving ladies-in-waiting to the Queen Mother, and the oldest surviving one. At the age of 80 she offered to resign and politely announced her decision to the Queen Mother, who promptly turned down the request. “Congratulations” came Dame Frances's reply. “You will feel marvellous after you are 80.” She remained at her post.

Dame Frances was to spend much of her life in service and accompanied the Queen Mother to the various houses she owned – principally Clarence House in London, Birkhall on the Balmoral estate, the Castle of Mey in Caithness, and the Royal Lodge at Windsor. But there were also long overseas tours, notably to Canada and Australia, where the schedules had to be strictly controlled and protocol managed. In such cases Dame Frances managed matters with tact, authority and a genial smile.

Frances Olivia Grenfell was born in St Leonards-on-Sea, a younger daughter of a banker, Arthur Grenfell and his second wife, Hilda Lyttelton (his first wife had died young_. She was educated at St Paul’s School and then joined the Peace Pledge Movement, which promoted pacifism. In 1938 she went to Canada to stay with the Tweedsmuirs (the novelist John Buchan and his wife, Susan) who was the Governor General and there she met Lord Tweedsmuir’s aide-de-camp, Patrick Campbell-Preston, a young Black Watch officer. They became engaged after two months. On the outbreak of war he was sent to France but was captured serving with the Highland Division at St Valery in Normandy in 1940. He spent the rest of the war as a PoW, mostly in Colditz with such notable prisoners as Douglas Bader, the pilot.

Dame Frances served during the war in Oban as an ‘immobile’ Wren - so named as they operated near their family home. After the war her husband returned to his regiment and they lived in Argyll. He died after a car crash in 1960.

Five years later Dame Frances was appointed a lady-in-waiting to the Queen Mother. The official title was Woman of the Bedchamber. It was a post for which she was entirely unprepared: for her first meeting with the Queen Mother, she borrowed a smart outfit from her cousin, the actress, Joyce Grenfell. The job had its grand moments, however: breakfast in bed brought to the bedroom by a footman and passed to a housemaid. But there was a strict formality: ladies-in-waiting curtseyed to the Queen Mother once in the morning, once at lunch and on saying goodnight.

There followed years of devoted service at home and abroad at official events and more domestic private occasions. It was, for example, Dame Frances who invariably took sensitive letters into the Queen Mother. Hugo Vickers (who edited her autobiography, The Rich Spoils of Time) has recalled, “Frances would just go straight in with the letter.”

There were glamorous outings to race meetings, the theatre and ballet – three of the Queen Mother’s passions – and meeting the celebrities of the day. Noël Coward told Dame Frances how to congratulate actors after an appalling play: “Just say, ‘Darling – what a night!’”

But it was the visits to the Castle of Mey and Birkhall that Dame Frances remembered with special pleasure in her book. She wrote how the Queen Mother was always relaxed and at ease in Scotland, and recalled when the Queen Mother became interested in fossils. The two explored the windy seashore by the Castle of Mey bashing stones with two delicate, silver-headed gavels.

The Queen Mother loved her picnics around Balmoral, especially at the old Schoolhouse by the River Gairn and the Lodge at Loch Callater. Dame Frances described the Queen Mother dressed in "four jerseys, two headscarves and an enormous tent-like mac lined in camel hair, and all to be seen will be a tiny pair of blue hands and a few flashing diamonds".

When not on duty Dame Frances lived in a fine house, Inverawe, on the shores of Loch Etive. She had regular visits from her family – she had 13 grandchildren and 21 great-grandchildren – and was a much-admired figure in Argyll. She had served in the 1950s as District Commissioner for the Girl Guides and in the 1970s was chairman of the Children’s Hearing Panel, where her secretary was the young Donald Dewar. “Watch him”, she told her son Robert, “He’s going far.” Dame Frances also set up a Marriage Guidance Council in Oban and served as a Samaritan in London into her nineties.

She made the house over to her son Robert who established the highly successful Inverawe Smoked Fisheries business. “My mother just jelled with people – certainly did so for 37 years with the Queen Mother", he says. "She was always tactful and courteous and spoke to anyone – she was an excellent listener – and did so with a genuine interest in their affairs.”

She was created a DCVO in 1990 and is survived by her two sons and two daughters.