Donald Trump's Niece, Mary Trump, Is Revealed as Joe Biden's Debate Guest: 'The Stakes Are Far Too High'

Donald Trump's niece, Mary Trump, is slamming her uncle's "narcissism and cruelty" and what she calls a "sense of inferiority" ahead of the June 27 debate between him and President Joe Biden.

Mary will be on hand in Atlanta on Thursday night as a guest of Biden, telling journalists about her uncle's character after the event wraps.

In a statement shared with PEOPLE, Mary explained why she chose to partner with her uncle's political rival during a tense election year.

“For my whole life I have witnessed my uncle’s narcissism and cruelty," she said in the statement. "His sense of inferiority has always driven his jealousy and his pathological need to dominate others and this is information that is crucially important for the American people to have in advance of the most important election of our lifetimes.“

Mary, 59, is a vocal critic of Donald's, and released a book about him in 2020 titled Too Much and Never Enough: How My Family Created the World's Most Dangerous Man.

In her statement ahead of the debate, she said she would be attending the event on behalf of Biden's campaign "to remind everyone who Donald is as a person and how he would rule as a president because the stakes are far too high for us to get this wrong: We cannot afford to allow Donald Trump anywhere near the levers of power again.“

"Donald cannot be trusted and we must recognize that his last administration was simply a warm-up for much worse to come just as January 6th was a dress rehearsal for a man who will stop at nothing to ascend, once again, to this country’s highest office," she added. "He is desperate for power and has shown himself both unworthy of wielding it and obsessed with regaining it purely for his own benefit. He must be stopped.“

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Mary claimed that even those in Trump's "own inner circle" believe he is unfit for office, saying in the statement: "Think about the countless former aides who have been brave enough to recount their stories. They describe a man so deeply unhinged, so insecure that he would do anything – including inciting a violent mob to storm our nation’s Capitol."

The first 2024 presidential debate between Biden and Trump is scheduled to begin at 9 p.m. EDT on Thursday, June 27. It will be held in CNN's Atlanta studios, and moderated without a studio audience by anchors Jake Tapper and Dana Bash.