Trump 'has been institutionalized for most of his adult life’ -- and 5 other shocking revelations from Mary Trump’s book
President Donald Trump at a campaign rally in Tulsa (screengrab)

Excerpts are coming out from Mary Trump's tell-all book -- and some of the revelations are lurid.

The president and other family members have unsuccessfully tried to block publication of their niece's upcoming book, “Too Much and Never Enough: How My Family Created the World’s Most Dangerous Man,” but Simon & Schuster is moving up the publication date to July 14.

Here are five of the most shocking revelations for newly published excerpts:

• Donald Trump paid a proxy as a high schooler to take the SAT on his behalf, and that high score helped the future president get into the University of Pennsylvania’s prestigious Wharton business school -- which he has boasted was "super genius stuff."

• Mary Trump, who's a clinical psychologist, believes her uncle displays all nine clinical criteria for narcissism, but wrote that he likely suffers from a variety of additional mental or psychological disorders that explain his behavior. “Donald has been institutionalized for most of his adult life," she wrote, "so there is no way to know how he would thrive, or even survive, on his own in the real world.”

• As a boy, Donald Trump learned to lie to boost his standing in the eyes of his domineering father, Fred Trump, who disdained weakness and owning up to mistakes. “By limiting Donald’s access to his own feelings and rendering many of them unacceptable," Mary Trump wrote, "Fred perverted his son’s perception of the world and damaged his ability to live in it.”

• Fred Trump rejected his namesake son, Mary's father, and the family sent Fred Trump Jr. to the hospital to die alone from an alcohol-related heart attack in 1981, when he was 43. Donald Trump instead went to the movies, she wrote.

• The future president cruelly tormented his younger brother Robert Trump for his perceived weakness, and repeatedly hid his favorite toys. Donald Trump pretended he didn't know where the Tonka trucks were, and when his brother threw a tantrum he "threatened to dismantle the trucks in front of him if he didn’t stop crying.”

• Mary Trump describes her grandfather as a “high-functioning sociopath," and says the future president was warped by the abuse heaped on Fred Trump Jr. by their father and their mother's serious illness when he was a toddler. "Having been abandoned by his mother for at least a year, and having his father fail not only to meet his needs but to make him feel safe or loved, valued or mirrored, Donald suffered deprivations that would scar him for life."