Campaign revealed she had pneumonia after candidate stumbled on Sept. 11th, and she's had light schedule since with the exception of yesterday

Clinton has no events scheduled for Thursday or Friday, either

Campaign indicated she is prepping for the all-important debate Monday

After a packed schedule on Monday, Clinton's only events were by phone: a radio interview and a national security meeting

Hillary Clinton appeared at no public events Tuesday with less than two months before the election, and rival Donald Trump promptly ridiculed her 'taking the day off.'

Although Clinton held a packed day of events Monday, as she spoke briefly to reporters, attended a rally, and met with world leaders who can't vote in the election, her only events Tuesday took place by phone.

She called in to the Steve Harvey Radio show and held a conference call with her national security advisers

Trump, who held two rallies in swing state North Carolina on Tuesday, mocked his opponent on Twitter. 'Hillary Clinton is taking the day off again, she needs to rest. Sleep well Hillary - see you at the debate!' he wrote.

It was only the latest dig on Clinton by Trump, who has repeatedly mocked his rival's 'stamina,' although he wished her well after her campaign revealed her pneumonia diagnosis after a televised stumble on Sept. 11th.

WIDE AWAKE: Hillary Clinton attended a campaign rally in Philadelphia Monday, but had no public events Tuesday, with less than two months before Election Day

Donald Trump told Hillary Clinton to 'sleep well' after she took a day off the campaign trail Tuesday

Trump also took a shot at Clinton's Tuesday event staged inside an airport hangar with her campaign plane in the background, and claimed to have invented the staging

Trump brought up 'whatever she has been doing' in another tweet

Collapse: Hillary took a tumble as she attempted to leave the 9/11 Memorial on September 11

Clinton hasn't exactly disappeared. She attended a campaign event in Philadelphia Monday and has one scheduled in Florida Wednesday – though she has no events scheduled for Thursday or Friday.

Her campaign nixed a planned fundraiser in North Carolina Tuesday, even as Trump attended two rallies.

'Small NC town prepares for Trump rally; Clinton postpones Chapel Hill event,' read the headline on the local CBS affiliate's web site.

Some outlets reported Clinton was prepping for the debate, although her campaign didn't respond to a specific inquiry from DailyMail.com about her schedule for the day.

Since she disclosed her illness, Clinton visited North Carolina last Thursday, attended two galas in D.C. and delivered a speech and had a down day on Sunday.

On Monday she spoke to reporters, rallied students at Temple University, attended a fundraiser, and held three bilateral meetings with world leaders at the UN, wrapping up around 10:15 pm in New York City to head home.

Trump continues to pepper his language about Clinton with descriptions of her vigor, just as he did with 'low energy' Jeb Bush during the campaign.

Trump jabbed Clinton for holding an event in front of her plane 'like I have been doing'

I DON'T MIND: Clinton's aides must balance the need to keep her in the public eye while also getting her ready for Monday's high-stakes debate

Clinton visited the UN for bilateral meetings Monday night

NIGHT SHIFT: Clinton met with Japanese Prime Minister Shinzo Abe in New York Monday evening

PILLOW TALK: Clinton also met with Ukraine's President Petro Poroshenko

PYRAMID SCHEME: Clinton's campaign staff thought it would be a good idea to have the candidate, who was diagnosed with pneumonia 12 days ago, to meet with world leaders including Egyptian President Abdel Fattah el-Sisi until after 10:00 pm Monday night

WAKE-UP CALL: Trump told Fox News host Bill O'Reilly he's not looking to bring up the Monica Lewinsky scandal during the debate

One advantage to traditional campaign events is there are voters there

Discussing ISIS on Fox News Monday night, Trump condemned 'Hillary Clinton, who is so weak.'

With a tightening race, the date is positioned to become a signal event.

Trump says he isn't 'looking' to bring up the Monica Lewinsky scandal – as long as Clinton shows him 'respect.'

Clinton told the Steve Harvey radio show, 'I am going to do my very best to communicate as clearly and fearlessly as I can in the face of the insults and the attacks and the bullying and the bigotry that we have seen coming from my opponent.'

To try to throw Trump off, Clinton's advisers 'have been looking for a one-line retort that will be a memorable moment from the contest,' CNN reported.

Clinton has spent hours watching a highlight reel of Trump's Republican primary debates, according to several people familiar with her debate preparation. She took notes on what agitated him, particularly in his exchanges with rival Ted Cruz, and studied his style.