Donald Trump Donald John TrumpBubba Wallace to be driver of Michael Jordan, Denny Hamlin NASCAR team Graham: GOP will confirm Trump's Supreme Court nominee before the election Southwest Airlines, unions call for six-month extension of government aid MORE mocked Hillary Clinton Hillary Diane Rodham ClintonJoe Biden looks to expand election battleground into Trump country Biden leads Trump by 12 points among Catholic voters: poll The Hill's Campaign Report: Biden goes on offense MORE for stumbling during a 9/11 memorial event last month, imitating her fall that doctors chalked up to dehydration.

It's a personal attack Republicans have warned Trump, the party's presidential nominee, to avoid. But while he has refused to engage on the issue, even publicly wishing her well, his tone changed Saturday night after an especially heated week.

ADVERTISEMENT "Here's a woman — she's supposed to fight all these different things — and she can't make it 15 feet to her car, give me a break," he said during a rally in Manheim, Pa. Trump then began to mimic Clinton, the Democratic presidential nominee, toppling over, stepping away from his microphone and pretending to stumble. "She's home resting right now, getting ready for her next speech, which is going to be 15 minutes in about two to three days. Folks, we need stamina, we need energy, we need people that are going to turn deals around," Trump said.

Cellphone video of Clinton stumbling as aides led her to a car at a 9/11 memorial in New York City last month prompted the campaign to admit that she had been diagnosed with pneumonia, which ultimately led to dehydration.

It played into conservative theories that Clinton is not as healthy as she claims. Trump allies have long questioned Clinton's health.

But Clinton's staffers pushed back at those rumors by releasing more of Clinton's health records, including a note from her doctor outlining her care.

The diagnosis led her to take a few days off from the campaign trail before returning.