Unmissable in a red Catherine Walker coat and matching Gina Foster hat, the Princess of Wales dominated media coverage of the annual Commonwealth Day Service of Celebration this week.

It was the first time in two years that Catherine and her father-in-law King Charles had attended the service at Westminster Abbey, because of their respective cancer treatments. And it was the princess, not the monarch, who was pictured on newspaper front pages the next day.

Just like the late Queen Elizabeth, who stood out from the crowd with the bright colours she wore, Catherine increasingly seems to wear striking and elegant outfits of a single colour that emphasise her importance to the Royal Family.

Camilla is Queen, but Catherine is making clear that she is ready to take that role when her time comes.

Her impressive appearance this week made me think back many years to the first occasion I met Catherine – or Kate Middleton, as she was known by everyone then.

It was at the launch party for Simon Sebag Montefiore’s biography Young Stalin in 2007, when Catherine had briefly split from Prince William.

Catherine, then aged 25, attended the event with her sister, Pippa Middleton, and chatted to me in a group with Sebag Montefiore’s sister-in-law, the TV presenter Tara Palmer-Tomkinson, who sadly died a decade later at the age of 45.

Tara, the daughter of two of King Charles’s closest friends, Charles and Patti Palmer-Tomkinson, had known Prince William since he was a little boy and was not shy about speaking intimately about him to Catherine at the party at Asprey jewellers in Mayfair.

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Unmissable in a red Catherine Walker coat and matching Gina Foster hat, the Princess of Wales dominated media coverage of the annual Commonwealth Day Service of Celebration this week

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I first met Catherine at a book launch in 2007, when Catherine had briefly split from Prince William. She is pictured at the event with her sister Pippa

While I made small-talk to Catherine about Montefiore’s book and how she knew the author, Tara, typically, got straight down to what everyone really wanted to know about: Catherine’s break-up with William. The split had been a big story since it had been disclosed a few months earlier.

‘How are you doing?’ Tara asked her.

Catherine replied, ‘Fine’, and started blushing.

‘It must be so hard…’ Tara persisted.

‘Really, it’s fine,’ Catherine replied, firmly, if uncomfortably.

She made clear with her body language that she didn’t wish to discuss the subject, and the conversation moved swiftly on to happier and less fraught matters.

At that time, Catherine was seen as a party-loving girlfriend of William, but my first encounter with her taught me that she was a tough cookie who wasn’t going to be inveigled into saying something she didn’t want to say by anyone – not even a close friend of the royals.

Indeed, she reminded me of members of the Royal Family, much older than herself, who have the uncanny ability to make small-talk with anyone (even tiresome social diarists) without giving anything anyway.

They usually manage to turn the conversation around and force the questioner do the talking.

Fortunately for the future of the Royal Family, Catherine was reunited with William a couple of months later. Although she has changed in many ways since our fleeting first encounter – becoming, for example, a confident public speaker – there was a hint of that inner steel which has served her so well in the years since.

Through the trauma of cancer treatment over the past year, she has emerged as an even more impressive figure who commands attention at big royal events such as the Commonwealth Day Service.

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