The Duchess of York is believed to have found her way back into the good books of the Royal Family thanks to the kindness of Queen Consort Camilla.
Sarah Ferguson has found an ally in Camilla and reportedly strengthened their bond over Christmas.
Fergie, who married Prince Andrew in 1986, was left on the outside of royal life following the end of the couple's 10-year marriage which saw them have two children - Princess Beatrice and Princess Eugenie.
With a new monarch on the throne, the Duchess of York, who still lives with Prince Andrew, was invited to join the royals for Christmas lunch at Sandringham and the following day's shoot for the first time since 1992.
For 30 years, Prince Andrew has taken Princesses Beatrice and Eugenie to the Sandringham estate for the festive celebrations with Sarah not invited due to poor relations with the late Prince Philip.
It is understood Fergie was banned from attending Royal Family gatherings after she was caught on camera having her toe sucked by financial adviser John Bryan.
The scandal rocked The Firm and marked the beginning of a very difficult relationship between Fergie and her in-laws.
But a source told the Mail on Sunday that Camilla has a 'powerful advocate' in the Duchess of York, who is "smart enough to play the game with Camilla".
They said: "Camilla likes Sarah. They're both gentry. They share a love of horses and Fergie will be smart enough to play the game with Camilla and realise she is the power behind the King. That she must be nice to them and support them."
Sources believe that the Duke and Duchess of York were offered the use of Wood Farm - the cottage on Sandringham Estate where Philip spent his retirement - for the Christmas festivities.
The source said: "There was Fergie, in the thick of it, chatting away to the King and Queen Consort on the Boxing Day shoot. Philip would never have allowed that.
"There's a feeling that, no matter what Sarah's personal faults – and she can be like Marmite in that respect – she has been a good mother to the girls and loyal to Andrew."