Despite this emotional reserve, she was compassionate. During the war the two princesses were moved to the comparative safety of Windsor Castle. They were subjected to the occasional air raid but never to the full force of the Blitz. Even so, Elizabeth took a keen and caring interest in the welfare of those more directly affected by the carnage. When the battleship Royal Oak was torpedoed by a German U-boat that had slipped through the defences of the northern naval base Scapa Flow in October 1939, with the loss of 800 lives, she exclaimed: ‘It can’t be! All those nice sailors.’ That Christmas the deaths were still on her mind, as she remarked: ‘Perhaps we are too happy. I keep thinking of those sailors and what Christmas must have been like in their homes.’ And when she read the name of someone she knew who had died in combat, usually an officer who had been briefly stationed at the castle, she would write to the mother ‘and give her a little picture of how much she had appreciated him at Windsor and what they had talked about,’ said Crawfie. ‘That was entirely her own idea.’ More mundanely but very much in character, she would instruct her more rumbustious sister not to point and laugh at anyone wearing a ‘funny hat’.

She subscribed to Louis XIV’s view that punctuality is the politeness of princes (and princesses) and was always on time. She was obedient – her only transgression of any note, apart from the occasional nursery scrap with her sister, was when she, aged seven or eight years old, turned an ornamental inkpot over the head of the mademoiselle employed to teach her French.

She was discreet. When the King flew to Italy in 1944, he told his daughter where he was going. His trip was classified as top secret and Elizabeth kept the information to herself and didn’t even share it with those women – Allah, Bobo MacDonald and Crawfie – who she was so close to. She also acquired the royal family habit of banishing unpleasant thoughts and people from her mind. Uncle David was not dead, but he might as well have been. The Duke of Windsor had been particularly fond of his niece. He had been a frequent visitor to the house in Piccadilly and took a childish delight in joining her in her games, but since the abdication he had ceased to exist. ‘In the palace and the castle his name was never mentioned,’ Crawfie noted.