When Kate Middleton stepped out in a heavenly blue Elie Saab ensemble for the first day of Royal Ascot, it was an all-time fashion peak.
Indeed the dreamy designer collaborating with one of the biggest trend-setters in fashion today was something royal fashion-enthusiasts had only dreamed about.
But then, something else quite unique happened.
After feasting our eyeballs on Kate's divine design, we saw another royal step out in the same stunning shade of blue. And then another... and then another.
So to what did we owe this indigo-inspired pleasure?
Well, it seems something rather special.
Alongside Kate stood no less than four other blue-clad royals on day one of the race-day festivities.
Her Majesty herself wore a shade of the gorgeous colour. Then came Beatrice, who also looked incredible in a blue embroided ensemble complete with a matching wide brim hat.
Even newlywed Princess Eugenie stepped out in a striking blue design - her shade of turquoise being slightly bolder than the others.
Finally, Zara Tindall chose to perch a baby blue hat atop her signature blonde 'do in addition to her floral ensemble.
The seemingly coincidental circumstance was one that doesn't often occur in royal circles.
In fact, the royals usually make an active effort to ensure they don't all wear the same colour at the same time - just look at Kate and Meghan, who are often seen at events in strikingly different colour palettes (albeit glamorous ones!).
So to see no less than five royals don the same hue in a single day at the same event was something quite extraordinary - and it turns out it could have been for a very meaningful reason.
Believed to be the Queen's favourite colour, Her Majesty wears the shade nearly three times more than she wears any other shade, according to some very dedicated calculations.
Indeed Vogue magazine once reported that the Queen chose to don the colour blue to no less than for 29 per cent of her state engagements over the course of a year in 2012.
So while it came as no surprise to see the Queen wear the beautiful tone, perhaps Kate, Beatrice, Eugenie and Zara all chose to wear the colour to pay tribute to their ultimate Queen and grandmother (in-law for Kate!).
WATCH: Royals arrive wearing white at state banquet with President Trump. Story continues after video...
It wouldn't be the first time we've seen the royals share a special tribute via their wardrobe.
As seen in the video above, the Queen's fellows Kate, Camilla and Anne, Princess Royal all opted to wear white to a State Banquet which was held for President Trump's visit.
And according to an expert, there could have been a very meaningful reason for it.
"White of course is the colour of peace and the colour of new beginnings," colour expert Gabi Winters explained.
"Coincidentally the psychological meaning behind this uncommon colour choice is very fitting when it comes to renewing and celebrating diplomatic ties between different nations."
She also explained that the colour white can represent a blank canvas on which to be written upon.
This would definitely make sense given that the royals were dining with international politicians.
With that being said, making a meaningful statement through fashion is something we'd love to see more of - long may the fashionable royal tributes last!