President Donald Trump revealed a dark secret about himself when he accepted the inaugural FIFA peace prize last week, according to his niece.

Mary Trump, a psychologist and author, argued in a new Substack essay that Trump's exuberance over the "fabricated and meaningless" FIFA prize was reminiscent of how "desperately" Trump is seeking the love of his parents. She pointed to his statement after FIFA president Gianni Infantino handed him the prize.

"I’m going to wear it right now. This is truly one of the great honors of my life," Trump recounter her uncle saying at the ceremony.

"If Donald had any self-awareness at all, which of course he does not, he’d be embarrassed and ashamed," Trump wrote in the essay. "He would know what we know—that he is being mocked."

Trump went on to discuss how her uncle's father, Fred Trump, was a "patriarchal authoritarian sociopath" who was incapable of loving his son, the current president. That left a huge void in Trump's life that he now seeks to fill with other pursuits, Trump argued.

She also warned that "all of us are paying the price" because of this void in her uncle's life.

"That is why Donald constantly needs more of everything else, believing that that will somehow fill the void," she wrote. "More money, more power, a bigger ballroom, more fake medals, more fake prizes, more fake honors. Maybe, he desperately hopes, someday that void will be filled. Maybe receiving more compliments, having more people grovel and degrade and debase themselves for him will finally make him feel whole."

"On some very dark level, Donald knows that’s impossible because as much as my grandfather wanted to convince Donald, and his other children, and his grandchildren that money is the only thing that matters, it can stand in for everything else, that isn’t true and never can be," she continued. "Nothing can replace kindness, empathy, or compassion. Nothing, certainly, can replace love. In his most terrified moments, Donald knows that. And all of us are paying the price for that knowledge."

Read the entire essay by clicking here.