The $450 black and white geometric print dress by Tory Burch is the latest in a long line of garments to demonstrate the 'Kate-effect', and no doubt won't be the last during the Duke and Duchess of Cambridge's royal tour.
Perfect for warm temperatures and chic yet comfortable, the short-sleeved open-knit dress with a cinched-in waist and elegant pleats is now in hot demand.
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Kate wore the winning number on Tuesday to the special playgroup where George met babies born within weeks of himself and William and Kate got to meet fellow first-time parents.
The dress, available on the Net-A-Porter website, is now out of stock. "Unfortunately this item has sold out. Add it to your wish list and we will tell you if more stock becomes available" reads the message on the site.
While the Rachel Riley Smocked Sailboat Dungarees that Prince George wore for his fun outing are still available online, it is surely only a matter of time before they too are snapped up.
Before the tour had even kicked off, Prince George's cuddly kangaroo backpack had sold out following its debut when the royal party arrived in Sydney on Monday, before flying on to Wellington, New Zealand.
After seeing the eight-month-old's adorable bag featuring the Australian animal carrying a joey, parents went out of their way to order the item online at the Australian Koala Foundation website.
Vendors have been forced to display a "This product is out of stock or unavailable" message to those hoping their tot will be as fashionable as Kate Middleton's little boy.