President Trump's niece Mary Trump went on the attack Wednesday in her first TV interview following the release of a new tell-all book about her uncle. "He is utterly incapable of leading this country. And it's dangerous to allow him to do so," Mary said on "Good Morning America."
Mary told George Stephanopoulos she had only one word to say to her uncle: "Resign!"
She was challenged on explosive claims in her scathing book about the Trump family, including that the president had a friend named Joe Shapiro take his SAT for him in 1964.
"I trust my sources," Mary said. She admitted she has no first-hand knowledge of the incident, and hadn't yet been born when it allegedly happened.
Inside Edition tracked down three former classmates of the president at the military school he attended. Each one refuted Mary's claim about the SATs.
"It was a closed society there," one said. "It was a military school. Nobody from the outside could come in."
"The teachers who are handing out the exams are standing by the door and checking every one of us that went in," another classmate said.
Former classmate Peter Ticktin also refuted the claim. "I know that Donald Trump was there, and I know that there was nobody else there pretending to be Donald Trump. It's just not a possibility," he said.
Mary Trump says the president's pugnacious style was shaped by his Father, Fred, who she calls a "sociopath."
"Certain feelings were not allowed ... sadness, the impulse to be kind, the impulse to be generous," Mary said.
The White House has denounced Mary Trump's book, which was officially released Tuesday, as filled with lies.