Prince Charles has spent many birthdays away from home celebrating with new acquaintances, but he's never started proceedings with a minute's silence.
Earlier in the day, media on the tour wondered if the party would indeed go on, considering the terrible atrocities happening in UK's close neighbour France.
But with 600 guests and months of preparation, calling off the event was never an option. It would disappoint too many and dishonour their hard work.
Instead, the Prince led a minute's silence, saying: "I hope all of you here will be able to join with me in expressing our particular sympathy and solidarity with everybody in France."
Clearly shaken, the heir to the throne went on to express his "utter and total horror" at the Paris terrorist atrocities. “Our hearts go out, as I’m sure you would agree, to all those who have been affected in the most dreadful way by these bestial attacks.”
It was a sombre but dignified opening to what was otherwise a joyous occasion on the Main Lawns of the Cottesloe Civic Centre, overlooking Cottesloe Beach, hosted by WA Premier Colin Barnett.
Guests including more than 100 children arrived to a wonderfully relaxed and colourful event with barbecue food stations showcasing WA specialties including Stirling Ranges beef tenderloin skewers, Mt Barker chicken sausages and Broome mackerel medallions.
There was a balloon animal maker entertaining the kids and fairy floss on the special kids' menu. A group of actors dressed in fabulous exaggerated native plant costumes delighted the invitees.
The guest list was deliberately diverse including locals who shared the Prince's birthday, people from the emergency services, community workers and representatives from the Australian charities the Prince works with.
Cricketer Adam Gilchrist, chef Antonio Carluccio and UK comedian Ben Elton were also among the throng. Elton with his Australian wife and their children lives part of the year in Freemantle and part in Sussex in the UK.
Earlier in the week he had penned a piece for a national newspaper suggesting that Australia should be a republic, with an Aboriginal elder as the Head of State, but when The Weekly asked him about the article, he explained his point was to highlight the need to recognise Indigenous Australians, not to denigrate the work of the royals.
"Clearly there's an enormous amount of respect and affection for the royal family. I think it would be hard to find anybody who didn't respect the contribution they've made to the stability of Australian democracy," he said. The warm sentiments for the Prince especially and his work in Australia continued from Janine Kirk, who runs his Prince's Charities Australia, another guest.
With food and wine flowing, and the band playing, the Prince in an open-necked pink shirt and light suit, and the Duchess in a delicate pansy print Anna Valentine dress which she had worn previously in Longreach on the opening day of her last Australian visit, walked through the revellers greeting the guests personally. It was a warm and convivial end to a successful day in WA.
In the distance, thunder started to rumble and it was time for the Prince to cut his extraordinary cake. Local cake maker Dany McEwen, who runs Marguerite Cakes, had sculpted a fun and dramatic creation with red velvet and chocolate layers and Toblerone filling, topped with a chocolate sail and decorated with native flowers, strawberries, macaroons and caramel popcorn.
But then the lightening started, with an impressive electric storm lighting up the sky and sheets of rain. Undeterred, His Royal Highness soldiered on saying he was really touched by the celebrations and declaring he'd had the best birthday ever in this special part of the country.
On Sunday the Prince and the Duchess will start off at church before a busy final day offering a few more opportunities to meet the public.