The next day, when Kate was photographed leaving Kensington Palace for her parents' house in Bucklebury, there was almost as much fuss over another dress – this time a frock from maternity retailer Seraphine, where Kate had been a customer during her pregnancy.
Within three hours of the sighting, the printed "Blossom" front-knot dress had completely sold out. Now there's a four-week waiting list with customers around the world clamoring to get a hold of one.
"The dress is one of our signature styles – we know she loves it as she has it in two other colors – she really loves the shape! And it's perfect post-pregnancy when you still have a little tummy," Seraphine founder Cecile Reinaud tells PEOPLE.
Echoing the sentiment of many new mothers around the world, Reinuad adds, "Hats off to her for actually showing what a woman looks like a day after she has given birth – I think it was quite brave of her."
The affordable French label founded by Reinaud in 2003 has been worn by celebrities such as Jessica Alba and Halle Berry but no one has affected sales quite like the young royal mom.
"Since Kate was first spotted in one of our dresses months ago, our company sales have seen an increase of 40 percent," says Reinaud who has personally delivered items for Kate to Kensington Palace. "We are the maternity brand she has worn the most which is great!"
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