Britain's Princess Eugenie of York and Jack Brooksbank are photographed in the White Drawing Room, Windsor Castle with from left, back row, Thomas Brooksbank, Nicola Brooksbank, George Brooksbank, Princess Beatrice, Sarah, Duchess of York, Prince Andrew, middle row, Prince George, Princess Charlotte, Queen Elizabeth II, Prince Philip, Maud Windsor, Louis De Givenchy, front row, Theodora Williams, Mia Tindall, Isla Phillips and Savannah Phillips. Picture: AP

London - Could this family wedding photo of the Duchess of York standing at Prince Philip’s shoulder be a  metaphor for things to  come?

For Philip, 97, it must have taken a great effort of will. For Fergie, perhaps, the hope of rehabilitation - the last time she appeared in the pictures of a formal Windsor family gathering was 27 years ago.

There were times during Princess Eugenie’s wedding ceremony when the Duchess’s mobile face took on a pensive look. Like any mother of the bride, her mind was dwelling on her daughter’s happiness.

Sitting in a front-row pew next to elder daughter Beatrice, with the Queen and Philip close behind, she was almost one of the family again.

But for the Duchess, this was a day of added poignance. On Monday, she is 59. What woman entering her 60th year doesn’t feel a need to be sure about her own future?

No one was more aware than Fergie herself that, among the 850 guests at her daughter’s wedding last Friday, the gossip wasn’t just about Eugenie and Jack, but about Sarah and Andrew.

For Philip, 97, it must have taken a great effort of will

Could they be the next to make their marriage vows? What a royal wedding that would be.

For more than 26 years, the twists and turns of this divorced couple have been entertaining many as much as they have been infuriating Andrew’s father, Prince Philip.

The manner in which they have lived virtually together almost as man and wife for many years is proof enough for most of their circle that one factor, and one factor alone, has stood between them remarrying - Prince Philip.

He has never forgiven the Duchess for humiliating his second son and embarrassing the family when pictures were published of her "financial adviser" John Bryan kissing her toes by a swimming pool in the South of France.

Just the other week when Fergie, together with her daughters Beatrice and Eugenie, was staying with the Queen, her morning departure was fixed with military precision for 10.30am prompt, 45  minutes before Philip was due to arrive - a gap calculated to be big enough to cope with any unforeseen delay.

Andrew and Fergie on their wedding day in 1986. Pictures: Reuters

In the past, when Fergie has been invited to tea with the Queen at Windsor Castle, he has made an excuse and left the room on the point of her arrival.

The Queen, it must be said, likes the Duchess. Despite her errors, extravagance and extraordinary ability to put her foot in it, she sees in Fergie a lively woman who has never lost her ability to make her favourite son happy. And she is proud of the way Sarah has raised her daughters.

Indeed, of all the royals, the Queen is the most relaxed about Andrew sharing Royal Lodge - the Queen Mother’s old home in Windsor Great Park - with his former wife.

More significantly, she is unlikely to raise any serious objections should they decide to remarry.

In the past, Andrew disdained the idea, saying that their untypical domestic arrangements for a divorced couple were intended to  make life easier for their two  daughters.