"Rest assured, I'm here at the @WhiteHouse w my family, feeling great, & working hard on behalf of children & the American people!" she tweeted.
Gossip has mounted in the 20 days since she was last seen, with President Donald Trump as he welcomed home three United States detainees from North Korea.
Four days later, the White House announced that the 48-year-old first lady had successfully undergone an "embolization" procedure to treat a benign kidney condition, and that there were no complications.
A Twitter "detective" claims to have found a cry for help in First Lady Melania Trump's tweet addressing her disappearance from public view and insisting she is fine.
Previously, Melania's spokesperson, Stephanie Grisham also slammed the rumors surrounding her absence from the public eye.
"She's doing great. She's looking at us, right there", the president reportedly said, pointing to a window.
Getty ImagesMelania has been out of the public eye for two weeks, but will she visit Canada next month?
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As you may be aware, her lack of public presence sparked a lot of different speculations.
On Twitter, some suggested her husband had actually written the tweet that appeared on her account on Wednesday.
The president later announced on Twitter that his wife was in "good spirits" and he would soon be visiting her in the hospital.
The first lady has not appeared in public since she returned to the White House after a minor kidney surgery on May 14. Others say she's cooperating with special counsel Robert Mueller.
Spokesperson Stephanie Grisham binned those rumours wholesale, telling Politico "we deal with conspiracy theories all the time", and reiterating that "she was hospitalized for nearly a week and is now home and recovering".
Still, suspicion was stirred on social media.
"They've never been joined at the hip", one White House official told CNN, explaining the first lady's wish to separate her individuality and character from that of her husband. I wouldn't characterize it as a long absence.