Just days after she wore this pretty, $80 polka-dot number from Topshop's maternity line, the dress has completely sold out online (though it can still be found in stores).
And it's no wonder – the dress (which Kate paired with a Ralph Lauren blazer and her signature black suede pumps) had PEOPLE StyleWatch Facebook commenters using one word, "classy," to describe her royal maternity style.
This is hardly the first outfit to have experienced the Duchess's magic touch. The Issa dress she wore to her engagement announcement, the perfume she wore on her wedding day and the L.K. Bennett pumps she adores have all been in scarce supply from the moment she's worn them in public.
Retailers including Zara, Reiss and MaxMara have all also seen Kate-worn clothing fly off shelves – partially because she tends to choose practical, affordable and flattering pieces, and because she looks so good wearing them.