Watch Stephen Colbert Joke About Why Melania Trump's Absence Was So "Weird" — VIDEO

The Late Show host had a little fun at the first lady's expense Monday night. Stephen Colbert joked about Melania Trump's recent absence from public life, saying she had not been seen in public for 25 days. "Well, I'm not surprised," he said, "it took that Shawshank guy years to tunnel out."

Melania actually made an appearance that afternoon at a White House reception honoring Gold Star military families Monday. While not unusual for a first lady to attend such an event, Melania's relatively long absence from the public eye did make her appearance more significant. A FLOTUS tweet following the event included a photo of her sitting next to the president in the East Room of the White House.

Before Monday's reception, the last public event the first lady attended was on May 10, when she and Donald Trump welcomed home three US citizens released from North Korean captivity at 3 a.m. aboard Air Force One.

On May 14, according to the White House, Melania underwent surgery for a benign kidney condition, and remained in a hospital near Washington D.C. for one week following her procedure. Colbert added:

They claimed she came home to the White House. Trump even welcomed her back in a tweet, in which he accidentally called her 'Melanie.' Awkward.

“Could you imagine if he called her the wrong name in bed?," the Late Night host asked. "She might hear it from down the hall!”

Numerous theories about Melania's hiatus from public life have sprung up in the last few weeks, especially because she had so recently announced her "Be Best" anti-bullying campaign. "How can you Be Best if you Be Missing?" tweeted actor and comedian Billy Eichner.

Rumors of a decision to leave the White House and move back to New York Cit, and even one far-fetched yarn about how Melania had decided to move in with the Obamas have kept Twitter conspiracists busy.

In response to growing speculation about the first lady's whereabouts, the FLOTUS Twitter account attempted to assure followers that she was back at the White House and doing well. However, Colbert, along with many other Twitter users, is skeptical that the tweet came from Melania herself.

“I have my doubts that Melania wrote [that tweet]," he said yesterday, after reading the statement aloud in his best impersonation of Donald Trump. "For one thing, Michelle Obama never said it in a speech," referring to the multiple occasions on which Melania has been said to have plagiarized her statements from old speeches. The first lady's staff has consistently denied allegations of plagiarism, most recently in May, releasing a statement accusing the media of "[lobbing] baseless accusations toward the First Lady and her new initiatives."

On Sunday, it was also announced that Melania will not be accompanying her husband to either the G7 summit in Canada this week, or the highly anticipated meeting with North Korean leader Kim Jong Un on June 12. Colbert said:

This is just weird. We’re used to our first ladies being out and about. Nancy Reagan was always out there telling kids to 'just say no'. Michelle Obama would sometimes just show up in people’s living rooms and tell them to drop and give her twenty.

The first lady's communications director, Stephanie Grisham, dismissed the rumors about Melania's absence to CNN, saying "Mrs. Trump has always been a strong and independent woman who puts her family, and certainly her health above all else, and that won't change over a rabid press corps. She's confident in what she is doing and in her role, and knows the rest is just speculation and nonsense."

Although Grisham confirmed to CNN that Melania would be at the Gold Star family event, it was closed to the press, with no opportunity for reporters to photograph the first lady in attendance. Colbert did not waste the opportunity to provide an "official" image of Melania at the event, saying, “I gotta say… she cleans up nice."

CNN reported that while at the event, Trump made a joke about Melania's absence and the surrounding public speculation, saying the media kept asking, "Where's Melania?"