The White House since released statements that the first lady would not be joining the president last weekend during his trip to Camp David nor would she be expected to attend the G7 summit in Quebec later this week.
Melania Trump has made her first public appearance in nearly a month, at a White House event to honour Gold Star families.
The First Lady joined President Trump for a reception welcoming families of service members killed in the line of duty.
As to what Melania's "little problem" might be - she had what was described as a successful and uncomplicated medical procedure on May 14 - no further explanation was forthcoming from the White House.
Yes, Melania shared photos of her appearance, but the photos were all taken from a distance and the event was closed to the press, so this is as good a look as we'll get for now.
Ms Trump's last public appearance was on May 10 when she accompanied her husband to Andrews Air Force Base to welcome home three Americans who had been held prisoner in North Korea.
"I see the media is working overtime speculating where I am & what I'm doing", the tweet said. Bennett noted that the first lady stayed at the hospital for five days and that the condition may have been more serious than the White House initially let on.
The President laughed off rumours his wife had left him ("Isn't that right, honey?") before asking "Did she leave him?" and pointing to Mrs Trump in her VIP seat.
A spokeswoman for Melania Trump on Monday slammed a "rabid press corps" for the wanton speculation about her condition and whereabouts.
During a press briefing Monday, Press Secretary North Korea announced the USA will not remove its sanctions and may even increase its maximum pressure campaign if denuclearize talks fail.
She is known for her privacy and White House independence, often breaking with her husband's schedule.
The President also talked about the strong economy during the event, the person inside the room said.
Jean Harris, a politics professor at the University of Scranton in Pennsylvania, says skipping Singapore makes some sense because there is no clear social role for a spouse amid the tensions of that meeting.