When picking a photographer to take a special portrait for a magazine cover shoot, the Duchess of Cornwall would have had her pick of snappers.
But she commissioned her stepdaughter-in-law the Duchess of Cambridge to take the all-important images - in a sign of their close and special connection.
Over the years their bond has been evident, with Camilla on hand to give the younger Kate a whole wealth of advice.
In the future, both women's husbands are destined to become King - meaning they are both currently primed to become Queen Consorts.
And with similar futures ahead, it seems Kate and Camilla are keen to support each other as they navigate royal life. Here we look at their bond....
Dating advice
Camilla and Kate's friendly bond goes all the way back to when the younger of the two women was first linked to her now husband Prince William.
Camilla joined the royal fold several years before Kate so knew what life was like within the Firm.
Kate had a lot to learn, and she needed to do it quickly as she took on the role of royal girlfriend.
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And it was Camilla who reportedly reached out to offer her future step-daughter-in-law a few words of advice, and they're very telling.
According to royal expert and biography Robert Lacey, Charles's wife had a little tip for Kate - but she struggled to follow it.
In his book, Battle of Brothers, Lacey writes: "Camilla had confided to Kate the secret of hanging on to a busy prince: fit your timetable - well, basically your whole life - around his."
However, despite Camilla's advice, Lacey claims that this wasn't really possible for Kate as William's diary was "un-fit-roundable".
Heartfelt gift
At the time of William and Kate's wedding, it seems Camilla was keen to cement her bond with her new stepdaughter-in-law by gifting her a personalised gold bracelet.
The chain-link bracelet features one single charm with engravings on either side, as is reported by Hello! Magazine.
Each side of the little disc features a monogram - both Kate's and Camilla's.
On one side is the letter 'C' for Catherine, Kate's given name, with a coronet and on the other is a 'C' for Camilla and a crown.
Kate has been seen wearing the bracelet in public a handful of times - including once at Wimbledon in 2011 and again during the Santa Barbara Polo Match as part of her official royal tour to California.
Stepping out together
In recent times, there have been several royal engagements that both Camilla and Kate have attended together.
Last year, the pair, along with their husbands attended the premiere of the James Bond movie No Time To Die together.
While last June, they also took part in a fun engagement in Cornwall with the Queen, where Camilla helped Her Majesty cut a cake using a ceremonial sword.
Earlier this year, they also made a joint visit, along with Prince Charles, to East London, where they met textiles students at a centre run by the Prince's Foundation.
The two women were seen happily chatting and sharing a joke as they toured the centred and looked at ease in each other's company.
They also appeared together and the Commonwealth Day service at Westminster Abbey and multiple times alongside each other during the Queen's Platinum Jubilee celebrations - including in two appearances on the Buckingham Palace balcony.
And during Trooping the Colour the pair along with Kate's children Prince George, Princess Charlotte and Prince Louis all rode in a carriage together.
Act of inconvenience
One particular lovely moment between the two women came in March this year during the Commonwealth Day service.
They were seen kissing each other on the cheeks and chatted warmly before taking part in the procession down the Westminster Abbey aisle.
In fact, body language expert Judi James noted how in that moment, Kate was keen to show her affection and closeness to Camilla by performing a huge "act of inconvenience".
Judi told the Mirror: "Kate touched Camilla’s arm with her left hand as an add-on gesture to suggest closeness and affection as they cheek-kissed.
"She also performed a huge ‘act of inconvenience’ to show respect, bending her knees to lower herself right down to plant her kiss on Camilla’s cheeks."
No upstaging
What do you think of the photos? Have your say in the comment section below.
Another day that saw the two royal women together was Remembrance Sunday last year during the service at the Cenotaph.
At the last minute, the Queen had to pull out of attending due to a sprained back and when they took the position on the Foreign Office balcony, Kate stood centre stage with Camilla and Sophie Wessex at her side.
Despite the positioning making Kate seem the more senior, body language expert Judi James said it appeared that Camilla was comfortable standing to the side.
However, that's not to say Kate isn't aware of Camilla's hierarchy in the family, according to royal expert Ingrid Seward.
She told the Mirror: "Prince Charles is not even King yet and the Royals are very careful about not upstaging each other. Kate will be keen not to upstage Camilla.
“She is aware of hierarchy and that it is Camilla’s turn."
