In the prologue of “Too Much and Never Enough,” Mary Trump writes: “The media failed to notice that not one member of Donald’s family, apart from his children, his son-in-law and his current wife, said a word in support of him during the entire campaign.” That doesn’t mean they had no opinions. The daughter of the president’s older brother, Freddy, who died in 1981, now shares some of hers — not just by airing the family’s dirty laundry, but by washing and folding it, too. (Mary Trump is a clinical psychologist whose diagnoses for her uncle are as varied and extensive as the fast food buffet he offered the Clemson Tigers when they visited the White House in 2019.)

[ Read Jennifer Szalai’s review of “Too Much and Never Enough.” ]

Here are seven insights gleaned from reading the first niece.

Nothing Donald Trump said during his campaign deviated from Mary Trump’s expectations of him.

“I was reminded of every family meal I’d ever attended during which Donald had talked about all of the women he considered ugly fat slobs or the men, usually more accomplished or powerful, he called losers,” she writes. “That kind of casual dehumanization of people was commonplace at the Trump dinner table.”

The author declined an invitation to an election night party in New York City.

Her reason: “I wouldn’t be able to contain my euphoria when Clinton’s victory was announced, and I didn’t want to be rude.” In the months following her uncle’s inauguration, “the smallest thing — seeing Donald’s face or hearing my own name, both of which happened dozens of times a day — took me back to the time when my father had withered and died beneath the cruelty and contempt of my grandfather. I had lost him when he was only 42 and I was 16. The horror of Donald’s cruelty was being magnified by the fact that his acts were now official U.S. policy, affecting millions of people.”

But, in April 2017, she did accept an invite to a White House celebration for her aunts’ birthdays.

At Trump International Hotel, the extended family “piled haphazardly into the two White House vans like a J.V. lacrosse team.” Upon arrival at their destination, Vice President Pence lurked “with a half-dead smile on his face, like the chaperone everybody wanted to avoid,” and guests were treated to a tour, during which Mary Trump “was surprised to see a half-eaten apple on the bedside table” in the Lincoln Bedroom. Dinner was brief, as Trump dinners usually are. Mashed potatoes were on the menu, prompting the president’s sister Maryanne to tell a favorite family story about “that night when Freddy dumped a bowl of mashed potatoes on Donald’s head because he was being such a brat.” When it was the author’s turn to take a picture with her uncle, she could “see the exhaustion behind the smile. It seemed that keeping up the cheerful facade was wearing on him.”

‘For Donald, lying was primarily a mode of self-aggrandizement meant to convince other people he was better than he actually was.’

According to Mary Trump, her father’s siblings were raised with a few core beliefs: lying was OK — in fact, it was “a way of life”; apologies and displays of emotion or vulnerability were verboten; and bullying was perfectly acceptable, if not encouraged. She tells a story about a young Donald Trump threatening to dismantle his younger brother’s favorite toy trucks: “Desperate to save them, Robert ran to his mother. Mary’s solution was to hide the trucks in the attic, effectively punishing Robert, who’d done nothing wrong, and leaving Donald feeling invincible. He wasn’t yet being rewarded for selfishness, obstinacy or cruelty, but he wasn’t being punished for those flaws, either.”

You do not want to be on the bad side of the Trump family.

Donald Trump’s father, Fred, never cared for Mary Trump’s mother, Linda, a former flight attendant from Florida whom he considered a gold digger. He turned a blind eye when his eldest son was sick and living with his young family in a frigid Trump-owned apartment with plastic sheeting over its rotting walls. Years later, after his son died, Fred would disinherit Mary and her brother; their uncle, Robert (of the toy trucks), explained: “Your grandfather didn’t want you or Fritz, or especially your mother, to get anything.” When the siblings threatened to sue for 20 percent of their grandfather’s estate, the family cut off the medical insurance that had been provided by Trump Management since they were born. “My brother depended upon this insurance to pay for my nephew’s crushing medical expenses,” Mary Trump writes. “William was out of the hospital by then, but he was still susceptible to seizures, which more than once had put him in a state of cardiac arrest so severe that he would not have survived without CPR. He still required round-the-clock nursing care.” The response from the lawyer representing Fred Trump’s estate: William’s parents should learn CPR.

The Trumps have a way with words.

Donald Trump, upon seeing his niece in a bathing suit: “You’re stacked.” Fred Trump’s advice to his son Freddy, who was suffering from alcoholism: “Just give it a quarter of a turn on the mental carburetor.” Fred Trump’s advice to his wife, who was frequently ill: “Everything’s great. Right, Toots? You just have to think positive.”

Mary Trump has a simple reason for writing this book.

“Donald, following the lead of my grandfather and with the complicity, silence and inaction of his siblings, destroyed my father. I can’t let him destroy my country.”

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