Though the Duchess of Cambridge has never attended Royal Ascot, the Queen's 90th birthday year would be the perfect time to start. And if Kate decides to accompany the monarch to the iconic racing event, the big question is what will the royal wear?
Kate has been to several other racing events and always managed to strike a balance between formal and fashionable.
For her Epsom Derby appearance in 2011, the royal rocked an ivory Joseph jacket over a Reiss dress, topping the look off with nude LK Bennett accessories.
And in 2013, pregnant Kate attended the Cheltenham races wearing a short camel-coloured coat with her trusty Aquatalia brown suede boots and a matching winter hat by Lock & Co.
So if her usual formal style is anything to go by, if Kate was to attend Ascot, she would likely to opt for a plain dress and coat/jacket look with contrastingly coloured accessories that all match.
The 34-year-old sometimes opts for prints, but generally prefers a plainer, block-coloured look.
The outfit will, no doubt, have structure – Kate favours a tailored ensemble as it lends a sense of formality.
A headpiece is a definite – it's obligatory in Ascot's Royal Enclosure and, what's more, it needs to have a solid base of at least four inches.
That should be a piece of cake for Kate, who is no stranger to headgear and often wears beautiful, intricate hats for formal events.
Her favourite milliners are Jane Taylor, Philip Treacy and Lock & Co, so she may well have commissioned one of the designers to create something bespoke for the occasion.