By Nick Maslow
September 12, 2016 at 04:19 PM EDT
JOSH EDELSON/AFP/Getty Images; David Paul Morris/Bloomberg via Getty Images

Donald Trump has wished Hillary Clinton a speedy recovery from pneumonia while arguing that her health is “an issue.”

“Like you, I see what I see,” Trump said on Fox & Friends early Monday. “The coughing fit was a week ago, so I assume that was pneumonia also. I mean, I would think it would have been, so something’s going on.”

He continued: “But I just hope she gets well and get back on the trail and we’ll be seeing her at the debate.”

However, Trump later added, “I think it’s an issue,” echoing his previous assertion that his rival has “no stamina.”

One day before, Clinton was seen struggling to get inside her van at the Sept. 11 memorial in lower Manhattan — video of which went viral. Her campaign said she became overheated and dehydrated, forcing her to leave the event early. Hours later, Clinton’s doctor Dr. Lisa Bardack said the presidential candidate has a case of pneumonia.

“Secretary Clinton has been experiencing a cough related to allergies. On Friday, during follow up evaluation of her prolonged cough, she was diagnosed with pneumonia,” Bardack said in a statement. “She was put on antibiotics, and advised to rest and modify her schedule. While at this morning’s event, she became overheated and dehydrated. I have just examined her and she is now re-hydrated and recovering nicely.”

Following Clinton’s stumble, she headed to her daughter Chelsea Clinton’s nearby apartment, where she later emerged and took a brief walk after resting for a couple hours. “It’s a beautiful day in New York,” she said, waving to a crowd of people.

On Monday, reports claimed several members of Clinton’s staff have been diagnosed with pneumonia. “Everyone’s been sick,” a campaign source told PEOPLE.

In the wake of Clinton’s diagnosis, she has canceled plans to visit California on Monday and Tuesday, opting to rest at her home in Chappaqua, New York.

Clinton released information on the state of her health last summer. A note from Bardack concluded that “she is in excellent physical condition and fit to serve as President of the United States.”

As for Trump’s health, Dr. Harold Bornstein claimed in a letter released in August that Trump’s health was “astonishingly excellent” and that he would be the “healthiest individual ever elected to the presidency.” According to NBC News, Bornstein admitted he wrote the letter in five minutes as a limo sent by Trump waited out his doctor’s office. 

In his interview with Fox & Friends on Monday, Trump said he is ready to share new data. “In fact, this last week, I took a physical, and I’ll be releasing when the numbers come in — hopefully they’re gonna be good. I think they’re gonna be good. I feel great. But when the numbers come in, I’ll be releasing very, very specific numbers.”

Clinton and Trump are set to face off at their first presidential debate on Monday, Sept. 26.