But as at first one, then all but one, of the marriages of the Queen and Prince Philip’s children came to their bitter ends, the methods by which they were raised appeared to be woefully inadequate training for dealing with the demands and pressures of the modern age.

Princess Margaret’s doomed marriage to man-about-town photographer Tony Armstrong-Jones in 1960 set a precedent. After numerous rows and affairs and two children, they divorced in 1978 – the first royal divorce since Henry VIII split from Anne of Cleves in 1540.

The divorces of the Queen’s children were not because they didn’t have a loving and united family life. Despite the demands of their parents’ position, they all always had family time together – Christmas at Sandringham, holidays at Balmoral and Windsor – but to a very large extent they were left to their own devices or to other people to educate and bring them up. Their career opportunities were limited and for some of them were mapped out in advance. They either went into the forces or they did charity work or, in most cases, both.

Trade has never worked for the immediate royal family as, whether they liked it or not, they were automatically separated by their heritage from the rest of the world. A royal prince or princess must act like one and not be seen to exploit their status for commercial gain, and this distinction has caused Prince Andrew some awkward moments. For the senior branch of the family, the isolation is reinforced by a protocol so rigid that even her children must bow or curtsey to the Queen.

This problem with commercial activities became even clearer in 2001, when Prince Edward’s wife Sophie was duped by the ‘fake sheikh’ Mazher Mahmood – an undercover reporter for the now-defunct News of the World – into revealing all kinds of indiscretions about the royal family. She was terrified of the repercussions when, in order to promote her company R-JH, she was recorded mocking the then prime minister, calling him President Blair, and referring to his wife Cherie as ‘horrid, absolutely horrid’. She also described the Queen as the ‘old dear’.