Democratic presidential candidate Hillary Clinton has canceled a campaign trip to California after news of her pneumonia diagnosis triggered new concerns over her health. One of Clinton’s aides announced the cancellation Sunday night. Clinton was scheduled to attend fundraisers Monday and Tuesday, and also to appear on The Ellen DeGeneres Show. But the trip is now off, as she has been advised by her doctor to rest. Clinton’s health has been the subject of numerous rumors throughout the campaign, with her Republican opponent Donald Trump repeatedly questioning whether she’s healthy enough to lead the country. At a 9/11 anniversary ceremony at ground zero on Sunday, Clinton abruptly left the event after appearing to faint. After initially claiming she’d simply “overheated,” her campaign admitted she had been diagnosed with pneumonia on Friday.