She may be a royal, but Kate Middleton is a fan of affordable fashion! The ever-relatable Duchess made an appearance at Green Junior School in London on Tuesday, Jan. 23 to discuss children's mental health awareness. For the outing, she donned a gorgeous, royal blue Séraphine maternity dress — and it turns out the frock is seriously budget-friendly. Ringing up at just $99, the A-line, three-quarter-sleeve dress would flatter anyone, and of course, Kate looked stunning in it.

According to the website, the dress is "made in premium stretch woven fabric," and "will adapt to your growing curves throughout your pregnancy." Perfect for any expectant mother, royalty included! And clearly, everyone wants to be like Kate — who wouldn't? — since the dress is completely sold out in every size online. Hopefully, it'll be back in stock soon, so every pregnant woman can feel like a princess!

kate middleton maternity dress getty

The mother-of-two seems to be a big fan of maternity brand Séraphine, as she's stepped out in the company's dresses several times in the past. Kate, who often recycles her looks, was most recently spotted wearing a floral-print, blue and green frock from Séraphine on Jan. 10. She previously wore it twice during her pregnancy with daughter Princess Charlotte. And that dress was even more affordable — it retails for $87!

Kensington Palace announced that Kate and Prince William are expecting their third child back in September, and since her official due date is in April 2018, there will be plenty more chances for Kate to flaunt her baby bump!

Because the couple is already parents to four-year-old Prince George and two-year-old Charlotte, William and Kate will definitely have their hands full with a third baby running around the house. Kate reportedly even had to "sweet talk a more 'reluctant' William into having a new addition." According to an insider, "Kate always wanted more than two children, it was William who needed to be persuaded. As one of three, Kate wanted at least three. William was more reluctant, not just because he was one of two, but because George was quite a difficult baby," the Sunday Express revealed. "Then they had [Charlotte] and she was a lot easier. Now the idea of a newborn doesn’t seem half as challenging, they’ve done it twice before and they’ve got all their staff in place," the insider continued.

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