The US first lady, 48, has not been seen in public since May 10.
Despite Trump's assurances, reporters didn't see any sign of the first lady watching from above.
Trump's absence from the public eye has prompted reactions, including jokes and conspiracy theories, from many social media users.
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However, Twitter users went into over-drive after the first lady assured she was fine, but the message had a particularly distinct way of writing which seemed eerily similar to that of her husband.
Black expressed sympathy for the first lady saying, "They treat her with the softest of kid gloves". Other than a tweet from her account that nearly definitely seems to have been written by her husband, we have no proof that she is even still alive.
Where in the world is Melania Trump?
"Not that this will deter the conspiracy theorists, but I saw the First Lady walking with her aides in the West Wing yesterday afternoon", CNBC's Eamon Javers tweeted on Wednesday.
Comedian Sarah Silverman retweeted Melania's tweet with her own comment: "Who is this? where's Melania?"
Viktor and Amalija Knavs moved to the Washington DC area after Trump won the election to help care for their grandson, 12-year-old Barron Trump, who is in a local school. While First Ladies are not obligated to share information about their physical health with the public, Melania's extended stay raised concerns.