Washington (CNN) It's been 20 days since the public has laid eyes on first lady Melania Trump.

In the early hours of May 10, Trump welcomed home three American hostages from North Korea, accompanying President Donald Trump to greet them on arrival at Joint Base Andrews; it would be the last time public appearance by the first lady for more than two weeks. Four days later, Trump was checked in to Walter Reed National Military Medical Center for what her spokeswoman Stephanie Grisham in a press release described as, "an embolization procedure to treat a benign kidney condition."

That statement was released post-procedure, allowing Grisham to add that it was "successful and there were no complications."

Yet 16 days later, the most anyone has heard from Trump has come via Twitter, with just one addressing her medical procedure.

A sincere thank you to Walter Reed Medical Unit @WRBethesda & to all who have send good wishes & prayers! I am feeling great & look forward to getting back home @WhiteHouse soon.

"A sincere thank you to Walter Reed Medical Unit @WRBethesda & to all who have send good wishes & prayers! I am feeling great & look forward to getting back home @WhiteHouse soon.

The first lady tweeted Wednesday that she's "working hard" and "feeling great."

I see the media is working overtime speculating where I am & what I'm doing. Rest assured, I'm here at the @WhiteHouse w my family, feeling great, & working hard on behalf of children & the American people! — Melania Trump (@FLOTUS) May 30, 2018

"I see the media is working overtime speculating where I am & what I'm doing. Rest assured, I'm here at the @WhiteHouse w my family, feeling great, & working hard on behalf of children & the American people!" she tweeted.

Since her almost week-long hospital stay, Trump has also tweeted about the school shooting in Santa Fe, Texas; the Navy SEAL who was awarded the Medal of Honor at a White House ceremony, which she did not attend, on May 24; and most recently, a tweet supporting the military in honor of Memorial Day.

Still, conspiracy theorists abound. Is the first lady OK, asks Twitter? Where is she? Why the long disappearance from public view?

Trump is just fine, it's the internet who's overreacting, according to Grisham.

"Sadly, we deal with conspiracy theories all the time -- so this is nothing new, just more silly nonsense," said Grisham, brushing off a rumor making the rounds that Trump has moved back to New York City.

Intensely private

Perhaps the concern or speculation also masks some frustration. After all, before her surprise -- to the public, at least -- medical procedure, they had seen quite a good deal of the first lady, who is often described as intensely private.

Nonetheless, she outshone the President, and the French President and first lady, in late-April, wearing a scene-stealing white hat to an official South Lawn arrival ceremony, garnering comparisons to Beyoncé.

She also put on the Trump administration's first State Dinner, for France, overseeing all of the decisions for the evening, from the White House Kitchen Garden herbs served as part of the meal to the silver, china, tablecloths and seat cushions. Wearing a sparkling Chanel Haute Couture gown, Trump was every inch appearing as a comfortable and capable first lady, almost 16 months into her tenure.

Results of a CNN poll conducted the following week confirmed just that -- the first lady was up 10 points to 57% in her favorability rating, making her again the most liked member of the Trump administration. She followed up her State Dinner appearance with the unveiling of "Be Best," her official platform. During her 11-minute speech , she underlined her commitment to spreading a message of social media kindness, as the President sat feet from his wife in the front row.

In short, she was on a roll.

Her own pace

However, in the grand scope of Trump's first lady schedule, a 20-day break, while long, isn't entirely out of the realm of possibility. She is one of the most independent first ladies in recent history, several times in the past year separating herself from her husband's travel plans, outings, rallies and, on more than one occasion, motorcades.

Trump has demonstrated she can and does like to do things at her own pace, taking months to hire a small but loyal staff -- less than half the size of typical East Wing employment rosters -- and taking on a rather broad range of causes under the vast umbrella of "helping children."

She also tweets when she feels like it, without waiting -- or even asking -- for West Wing approval or coordination.

"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. "She has always been independent."

Grisham said the disappearance from the public eye isn't unusual.

"I wouldn't characterize this as a long absence. She was hospitalized for almost a week and is now home and recovering. She has had several meetings internally with staff and will continue to do so this week."

In 2007, after a 2.5-hour, outpatient procedure at George Washington University Hospital to relieve pinched nerves in her neck, former first lady Laura Bush spent about a week with nothing on her official schedule, according to her former chief of staff, Anita McBride.

Trump may yet appear publicly over the next few days and she has remained occupied figuring out details for two White House events coming up on the calendar: the annual Congressional Picnic in June and July 4 events.