Sarah, Duchess of York and her daughters Princesses Beatrice and Eugenie call themselves "the tripod".
The 65-year-old author-and-philanthropist has shared that she and Beatrice, 36, and Eugenie, 34 - whose father is Prince Andrew - gave themselves the nickname as they always "support each other" through life's ups and downs.
Talking about being "spoiled" by her girls at Christmas, she told Britain's Bella magazine: "We spoil each other.
"We call each other 'the tripod' because we're always there to support each other and it's no different at Christmas.
"The girls and their husbands always get me the most thoughtful gifts and I try to pick something nice for them."
Beatrice is currently pregnant with her second child with her husband Edoardo Mapelli Mozzi - who has eight-year-old Wolfie from a previous relationship and three-year-old Sienna with the royal - and Eugenie has sons August, three, and Ernest, 15 months, with her spouse Jack Brooksbank.
And Sarah says Christmas is "all about the children".
She said: "Christmas is all about the children, so the grandchildren are the centre of things these days.
"We love Charades. I've never been a good cook so I'm lucky enough to leave it to others."
Sarah has spent the festive holiday at the royal family's Sandringham Estate in Norfolk - but she refuses to lift the lid on what goes down.
She said: "I've been lucky to be invited to spend Christmas with the royal family in recent years, but I wouldn't dream of talking about that."
Sarah divorced disgraced royal Prince Andrew in 1996 after a decade together, but they still remain close to this day.
The 64-year-old royal - who is the brother of King Charles and son of the late Queen Elizabeth and Prince Philip - has kept a low-profile since he came under fire over the fallout from his friendship with late paedophile billionaire Jeffrey Epstein and the claim he had sex with one of the financier’s trafficking victims Virginia Giuffre – which he denies.
Following the scandal, Andrew was stripped off his military titles and use of HRH.
However, Sarah promised his late mother that she would look out for him.
Sarah said on ITV’s ‘Loose Women’ about being there for Andrew during his “darkest times” despite not being a couple anymore: “We are longer divorced than married and I believe in the three c’s – communicate, compromise and compassion.
“That’s what I do with (Andrew.) We get on because, in the darkest time of my life, he was always there for me.
“In the darkest time of his life, I will be there for him. The Queen of England was there for him – his mum.
“I said to his mum before she died, ‘I will be there for him, I will help him on his journey.’
“We’ve all got journeys; we just need to be there with kindness and no judgement.”
