In December 1943, the King and Queen held a small dance at Windsor Castle for both their daughters. The King felt Elizabeth had missed out on the kind of socialising she should have had during her teenage years, and because of the war she hadn’t been able to have much fun. The Queen was impressed by the good manners of most of the young men invited, although Philip wasn’t one of them as he was confined to bed in Claridges Hotel (of all gloomy places the Queen noted).

Much to both the princesses’ delight, he was well enough to come to their pantomime and stay for the rest of the weekend. To raise funds for charity during the war and keep everyone entertained, the King had devised the idea of staging a pantomime every Christmas. That year it was Aladdin, with Princess Elizabeth as the principal boy. According to Crawfie, Princess Elizabeth acted better than she had ever done before. ‘I have never known Lilibet more animated. There was a sparkle about her that none of us had ever seen before.’ She went on to say: ‘Prince Philip was falling out of his seat with laughter.’ He then spent Christmas with them and was joined by his cousin David Milford Haven. According to Princess Elizabeth, ‘we had a gay time, with a film, dinner parties and dancing to the gramophone.’ The King’s private secretary, Tommy Lascelles, recalled ‘they frisked and capered away till near 1am’.

Looking back years later, Prince Philip described his wartime friendship with the royal family in a typically dismissive way: ‘I went to the theatre with them once, something like that. And then during the war, if I was here, I would call in and have a meal. I once or twice spent Christmas at Windsor, because I’d nowhere particular to go. I thought not all that much about it, I think. We used to correspond occasionally . . . But if you are related – I mean I knew half the people here, they were all relations – it isn’t so extraordinary to be on kind of family relationship terms. You don’t necessarily have to think about marriage.’

In his thank-you letter to the Queen after Christmas, Philip wrote he hoped that his behaviour ‘did not get too out of hand’. He added that he also hoped – if it was not too presumptuous – he could add Windsor to Broadlands (the Mountbatten home) and Coppins (the country home of the Duke and Duchess of Kent) to his favourite places: ‘That may give you some small idea of how much I appreciated the few days you were kind enough to let me spend with you.’