President Trump said Monday that he was surprised that Joseph R. Biden Jr.’s cancer diagnosis was not made public a “long time ago,” seeming to suggest without evidence that the former president’s cancer was not newly discovered and had been covered up.

Donald Trump Jr. accused the Dr. Jill Biden — who had a doctorate in education — of not detecting her husband's condition sooner.

"Melania and I are saddened to hear about Joe Biden's recent medical diagnosis," the president wrote on Sunday on social media.