The first lady accompanied the president to the speech at the United States Capitol wearing a navy version of the cream Gabriela Hearst evening dress she wore after her husband entered the White House in January.
The dress by the Uruguayan designer, who uses pre-existing fabrics in her work, had floral embroidery, sheer overlay and a matching navy mask.
When she designed the inauguration dress Ms Hearst explained that the embroidery featured the federal flowers of every state and territory in the United States.
“The Delaware flower is positioned at the heart level of The First Lady, from there, all the other flowers branch out. The pieces were made entirely in New York City,” the 44-year-old designer stated.
And the first lady’s outfit was seemingly a big hit on social media.
“So, yeah, it’s a presidential address to a joint session of Congress and using it as a look book is totally missing the point, but I want Jill Biden’s dress anyway,” tweeted @roseknows.
“Gabriela Hearst is quickly emerging as Jill Biden’s fashion favorite,” tweeted fashion writer Mekita Rivas.
MSNBC host Rachel Maddow poked fun at herself while describing the first lady’s dress for her show.
“I’m just saying what they tell me to tell you. I’ve worn the same black blazer for 13 years,” she said.
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