Stay calm everyone. It’s just a normal day….

Except for one slight difference:  today could be the day you finally own a piece of Kate Middleton’s wardrobe.

The gorgeous Zimmermann dress pictured on the left is about to go on sale.

But you better get in quick, fingers ready to click that buy button, and bank account topped up. Because if there’s one thing in the world we’re sure of? It’s that this Zimmerman dress Kate wore to the Sydney Royal Easter Show during the Royal Australian Tour is about to sell out in seconds.

It’s not called the ‘Kate effect’ for nothing, friends.

After all, it took less than eight minutes for the Diane Von Furstenberg wrap dress she wore in the Blue Mountains to fly off the racks, and three hours for a $35 Zara necklace she wore on a red carpet event to sell out completely.

Everything the woman touches/dons/ holds/ stares at intently is guaranteed to be an immediate success.

And that’s why women worldwide are collectively holding their breath right now, desperately hoping they make it through the online checkout before the Zimmerman site (likely) crashes.

If you’re keen to join in too, the Zimmerman Roamer Day Dress, part of the label’s summer swim collection, retails for a cool $495.00. You can purchase it here. 

And if for some reason it’s sold out by the time you click the ‘add to cart’ button, it’s definitely NOT because the Mamamia office just bought every single one…

For a full look at the other dresses worn by the Duchess on the Royal Tour, click through our gallery below:

Royal Family on Tour

Royal Couple in Adelaide

Royal couple in Adelaide

Royal couple in Adelaide

Royal Tour: The Duke and Duchess in Brisbane

Royal Tour: The Duke and Duchess in Brisbane

Royal Tour: The Duke and Duchess in Brisbane

Royal pair arrive in Canberra.

Royal couple at Uluru

Royal couple at Uluru

via Prince George of Cambridge Facebook

via Prince George of Cambridge Facebook

via Prince George of Cambridge Facebook

via Prince George of Cambridge Facebook

via Prince George of Cambridge Facebook

via Prince George of Cambridge Facebook

Royals back in Canberra

Royal couple in Adelaide

Royal couple at Uluru

Royal couple at Uluru

Royal couple at Uluru

Royal couple at Uluru

Royal couple at Uluru

Royal pair arrive in Canberra.

kate-44.jpg

The Duke and Duchess of Cambridge arrive at an Easter Sunday service in Sydney.

Royal Tour: The Duke and Duchess in Brisbane

Royal Tour: The Duke and Duchess in Brisbane

Royal Tour: The Duke and Duchess in Brisbane