The Duke and Duchess of York were married for 10 years, and went on to have two daughters together, Princess Beatrice, 30, and Princess Eugenie, 29.
But it was the Duke's work commitments with the military, and the media focus on the Duchess, which eventually led to their marriage breakdown, with the couple splitting in 1992, and then divorcing in 1996.
However their separation has always been amicable, something that had a great impact on their children.
Ingrid, who wrote a biography of Ferguson, added, “The girls love that their parents get on so well.”
And the royal exes who are said to be the "happiest divorced couple" get on so well, rumours are circling around the possibility of them rekindling their romance and remarrying.
The story couldn't have more different for their cousins, Prince William and Prince Harry.
Their parents, Prince Charles and Princess Diana, had a rough ride in their marriage, with the couple finally divorcing in 1996, after 15 years together.
Of course, the pain of their parents split was then compounded by their mother's untimely death after a Paris road accident in 1997.