Sarah Ferguson and Meghan Markle should have been the closest of friends inside the Royal Family - but a surprise announcement revealed that wasn't the case.
On paper, Fergie and Meghan have a lot in common and have faced similar issues inside The Firm.
Having been married to Prince Andrew for 10 years before the couple announced their "amicable split" in 1992, the Duchess of York knows all about the pressures of joining the Royal Family.
The 63-year-old has also experienced being pushed out to the cold by the royals and rebuilding her life in America, having been snubbed from weddings and other family engagement over the years.
While Fergie and Meghan got off to a great start, their relationship ever since has been rather rocky, culminating in Sarah admitting she "does not really know" her nephew's wife.
So where did it all begin for the two duchesses?
They met for for the fist time at Royal Lodge in Windsor in October 2016, as Harry wanted his aunt to be one of the first royals to meet his new partner.
But there was some last minute panic when the Sussexes realised that the late Queen was there - and Meghan had no idea how to curtsy.
Meghan said she didn't do any research into the Royal Family when she first started seeing Harry and "didn't fully understand what the job was".
In her controversial interview with Oprah Winfrey, Meghan recounted: "And I remember Harry and I are in the car and he says, 'okay, well, my, my grandmother's there. So you're going to meet her.'"
Luckily Fergie was on hand to quickly teach the former Suits actress about the royal tradition.
Questioning the need to be so formal, Meghan continued: "I thought that was part of the fanfare. I don't think that's what happens inside. And I said, but it's your grandmother. He goes, it's the Queen."
She then had to learn "very quickly" outside the front of Royal Lodge with Fergie. Meghan explained: "Right in front of the house we practised and ran in.
"Fergie ran out and said, 'Do you know how to curtsy?'... Apparently, I did a very deep curtsy, I don’t remember it, and then we sat there and we chatted."
Harry also recalled the moment in his memoir Spare, describing how his aunt helped Meghan to learn how to act in front of his grandmother.
"First stop, Royal Lodge. To meet Fergie, because Meg already knew Fergie's daughter Euge, and Jack, so this seemed a logical baby step," he wrote.
"Fergie came outside, somewhat aflutter, and said: 'Do you know how to curtsy?' Meg shook her head. Fergie demonstrated once. Meg imitated her.
"As we walked towards the door Fergie and I both leaned into Meg, whispering quick reminders. When you first meet the Queen it's Your Majesty. Thereafter it's just Ma'am. Rhymes with ham."
Fergie actually made her big comeback into the royal fold when she attended Meghan and Harry's wedding in May 2018.
While the the late Queen always had a soft spot for her former and 'favourite' daughter-in-law, Prince Philip reportedly described her as "odd" and "pointless", and she was snubbed from big royal events after a number of scandals.
Prince William, Peter Phillips and Zara Tindall were all page boys and bridesmaid at Fergie's wedding to Prince Andrew, but she didn't get an invite to Will's nuptials with Kate Middleton in 2011 or to those of Princess Anne's children.
But Sarah was given an olive branch when she was invited to the Sussex's big day - and was seen beaming as crowds shouted her name.
Speaking about what was going through her head on Good Morning Britain, she explained: "I felt like I was really happy for my friend Diana, who I love, and my mum and dad, and I felt honoured and grateful for Harry and Meghan to invite me.
"It was very kind of them and I think I can't thank them enough for doing that because it was nerve-wracking but I knew I was ready."
However, Fergie was sat to have been 'deeply upset' at being excluded from the 'inner sanctum' evening reception at Frogmore House.
Just months later in October that year, Fergie and Meghan crossed paths at Princess Eugenie's wedding to Jack Brooksbank.
But Fergie was reportedly fuming at Harry and Meghan for announcing their pregnancy news on the day of her daughter's wedding.
In their book Royals at War, investigative journalists Dylan Howard and Andy Tillett said: "Meghan put her foot in it when she decided that it would be the ideal moment to announce that she and Harry were expecting their first child.
"This was a huge social gaffe, even if you were not a royal – stealing the limelight from Eugenie, who was furious, as was her mother, Sarah."
Rumours of a feud intensified when Fergie tweeted a picture of her royal wedding outfit at the exact same moment the Duke and Duchess of Sussex announced they were having a baby.
Kensington Palace officially revealed the pregnancy at 8.40am on Fergie's 59th birthday, which is also when Sarah tweeted to thank her dress designer for the outfit she wore at Eugenie's wedding.
Fergie posted more messages explaining how "proud" she was of her daughter and new son-in-law - but she did not mention Harry or Meghan.
It seems any bad blood has now been put to bed as Fergie has regularly come out in defence of the couple.
When the Oprah interview was announced, Fergie said: 'I'm a great supporter of Oprah and everything that she does...I wouldn't presume to give advice to the Duke and Duchess of Sussex except to say to be happy."
Sarah has always said that Princess Diana, who she was particularly close with, would have been "proud" of Harry and Meghan.
Their paths would have next crossed at the late Queen's funeral - with Fergie confirming she did speak to Meghan, who looked "absolutely beautiful".
And she has refused to judge the Sussexes for their decision to quit as working royals - having a lot of experience in that department.
Earlier this month, she told the Daily Mail: "I don't believe that any single person has the right to judge another person. I'm not in a position myself to make any judgments.
"I have been judged all my life, and I have no judgment on the Sussexes."
Fergie then added that Princess Diana would be "incredibly proud" of her five grandchildren, which includes Harry and Meghan's son Archie and daughter Lilibet as well as Prince William and Kate Middleton's youngsters Prince George, Princess Charlotte and Prince Louis.
When it emerged that Harry and Meghan will be booted out of Frogmore Cottage, the Duchess of York said she "can understand" why her nephew would choose to pack up his life and move overseas.
In an interview with the Telegraph about her relationship with the Royal Family, the Duchess said: "I can't speak for [Harry].
"But I will say that after I got divorced, I spent 12 years in America, writing books, and it was a wonderful place for me. I felt free there."
Sarah added that she cannot "thank Americans enough" for their hospitality and so she "can understand why he would [do that]".
However, Fergie has recently admitted she "does not really know" the Duchess of Sussex well as they only met briefly, but she is sure that Meghan "really loves" Harry.
Asked if Meghan has damaged the Royal Family, Fergie told the Telegraph : "It is absolutely not my place to answer that. She has made Harry very happy, and that is so nice. Honestly, he's so happy with her. She really loves him.
"And I think that's beautiful – and that Diana would be proud of him and her lovely grandchildren."
Most recently, at the event to promote the book A Most Intriguing Lady, Fergie was asked what advice she would give Prince Harry and Meghan on having a public marriage.
"I think the best way to answer that is to really take hold and lead by example. I wouldn't give advice, I would say that your actions speak louder than words," she said.
Fergie who was also very close to Harry's mother, the late Princess Diana, also said that she and King Charles would be proud.
She added: "Diana and I, we played a lot and had a great time. I feel like she would be absolutely, and so is the King, so proud of their grandchildren and the family… I think forgiveness is key."