It's hard to imagine the famously slender Kate Middleton, Duchess of Cambridge as being big enough to require maternity wear, but she is, of course, heading that way.

Despite the royal family's official pregnancy announcement, we have yet to see the duchess' baby bump. Still, British label Issa is releasing a maternity version of her famous blue silk dress that she wore for her official engagement photos.

The original version of the dress sold out at UK department store Harvey Nichols only a few hours after the images were released and carried a price tag of £385 (about $600). The maternity reissue is available at UK boutique Blossom Mother and Child for £522 (about $820). All the extra fabric, we're guessing. 

Although there is nothing indicating Kate will repeat the dress during her pregnancy, let's be real—that shit is going to sell out.

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[via People]