Over the past week, President Trump seemed unusually subdued as the nation absorbed the news that his oldest child, Donald Jr., last year exulted in the prospect of getting derogatory information about Hillary Clinton from the Russian government. His son, the president said, “is a high-quality person,” “a wonderful young man.” It wasn’t until the end of the week that Trump defended his son’s decision to meet with the Russian lawyer who supposedly had the dirt: “Most people would have taken that meeting.”

There was simply no way this president was going to distance himself from his son’s actions, as he often does when a White House aide displeases him. In business and now in politics, Trump reserves his most effusive praise and his deepest trust for his flesh and blood, handing Ivanka a White House portfolio and his boys the run of the Trump enterprises.

Through the years, Trump has spoken about Donald Jr. very much as he describes himself: as a smart, ambitious, crafty guy who loves to win and has a mischievous streak that sometimes gets him in trouble. The president talks about his other adult children in similar ways. Ask about his kids, and Trump talks about how they’re like him — Ivanka, for example, has his business savvy and, as he once put it in an interview, his interest in sex.

Some psychologists have concluded that Trump sees his adult children as extensions of himself. “They are his world because they are him,” said Elan Golomb, a psychologist who wrote “Trapped in the Mirror: Adult Children of Narcissists in Their Struggle for Self .” “They don’t exist as separate entities. To a narcissist, the child is seen as ‘me.’ ”

Even his children agree that there is little separation between them and their celebrity father. “We’ve all made peace with the fact that we will never be able to achieve any level of autonomy ” from him, Ivanka told an interviewer in 2004. No wonder Trump places them in positions of power.

But the same instinct that induced the president to have Ivanka sit in for him briefly at the Group of 20 talks in Hamburg this month makes it difficult for him to distance himself from them or contradict them, as he often has when his staff advisers leave him angry or disappointed. Which raises this question: When Trump Jr. walked into that meeting to get the dirt on Clinton from the Russian lawyer, was he by default acting on his father’s behalf?

Presidents’ relatives have long served as distraction, embarrassment and vital support. President Jimmy Carter had to cope with an occasionally wayward brother, Billy. President Bill Clinton pardoned his half-brother Roger for a cocaine distribution conviction . At the other end of the scale, President John F. Kennedy relied on his brother Bobby as his attorney general and close adviser, and George W. Bush served a similar, though informal, role as counselor to his father, President George H.W. Bush.

But Trump is the first president who has arrived in office with his children as his most important and trusted advisers. Last year, when I asked Trump whom he would turn to in a moment of great crisis, he said it would not be any close friends — his friendships were mainly just business relationships, he said — but rather his adult children. “One thing I get a lot of credit for is my children,” he said. “They’re good children. And they’ve been smart. They went to great schools. Always got top-of-the line marks. . . . I get along with my children a lot.”

Trump grew up in a tight-knit family business. Groomed to take over Fred Trump’s New York real estate empire, Donald has always spoken of his father more as a businessman than as a parent. He has a standard few pat lines about Fred: He praises his father as an accomplished builder and role model who, alas, lacked his son’s unbridled ambition to play on the biggest stages. Trump has little to say about his mother, other than that he got his showmanship gene from her.

But ask Trump about his adult children, and a notoriously nonlinear storyteller suddenly grows effusive. The president virtually melts at any mention of Ivanka, and he rushes to defend her from criticism, as he did this month after the kerfuffle about the G-20 meeting. He exhibits a charming pride about sons Donald Jr. and Eric, repeatedly saying that his business is secure in their hands.

The Trump children know this role and accept it. Ivanka told Politico that what her father cared about when they were growing up was “respect. You would never hear us yelling at our parents or using a tone that was inappropriate or disrespectful. Even a tone.”

“Everything we’ve ever done, we’ve done as a family,” Eric told The Washington Post last year. “Every project we’ve ever built, we’ve built as a family. ‘The Apprentice’ we did as a family.”

President Trump has written about the importance of narcissism in his success and in the achievements of any business leader. He believes that an emphasis on his own ego not only promotes his brand, but gives him the confidence and standing to achieve more. And psychologists who study narcissism say such people often view their children as mirrors of themselves.

“The main issue with narcissists is that ‘people have to 100 percent agree with me about everything,’ ” Golomb said. “ ‘They have to be on my side.’ And they often are: Usually the parent is so fearful of criticism coming his way that he makes the child fearful of ever expressing their misery. They have to agree with and support the narcissistic parent.”

Which may explain why Trump often speaks of his children and his parents through the prism of his own life. At his father’s funeral, Trump talked mainly about himself. His siblings told stories about their father; Donald instead recited a list of his accomplishments, noting that his father had stood by him at each turn.

Gwenda Blair, the author of “The Trumps,” a multi-generational study of the family, concluded that Donald, his father, Fred, and his grandfather Friedrich Trump had a foundational similarity: “All three were energetic people who would do almost anything to make a buck; all three possessed a certain ruthlessness; all three had a free and easy way about the truth,” Blair wrote.

Of the president’s adult children, Donald Jr. is perhaps the most like his paternal lineage.

Donald Jr. is different from Ivanka and Eric in that he rebelled against his father. He was 15 in 1993, when his father married Marla Maples in the aftermath of his tabloid-chronicled divorce from Ivana Trump. The oldest child hit back hard against a wrenching, all-too-public trauma. “You don’t love us,” he told his father, according to an oft-cited account in Vanity Fair. “You don’t even love yourself. You just love your money.” But in that same era, Don Jr. defended his father with his fists, punching back at kids who taunted him about the divorce.

Donald Trump in those years was frank about his distance from his children, telling interviewers that he didn’t do things like change diapers or play ball with them. “Statistically, my children have a very bad shot,” he told Playboy in 1990. “Children of successful people are generally very, very troubled, not successful.” More recently, Trump joked that demographically, his kids should have ended up “in rehab.”

But today, he takes evident, abundant pride in the fact that they instead have become essential cogs in the family business. He told me in an interview last year that by bringing them into the enterprise in their teens — as his own father did with him — he turned their relationship around. “I mean, I love my children,” he said, “but I got to know my children much better after they graduated from college, in a sense, because they came to work here.”

Trump Jr. has said he was raised largely by his mother and her Czech parents. After the divorce, he refused to speak to his father for more than a year. But the icy relationship thawed with time. Trump Jr. told The Post’s Dan Zak last year that “it wasn’t a ‘Hey, son, let’s go play catch in the back yard’ kind of father-son relationship. . . . It was: ‘Hey, you’re back from school? Come down to the office.’ ”

Despite the early distance — which included boarding school and, in Don’s case, a couple of years of bartending, camping and partying in the Colorado Rockies — the Trump children developed an abiding loyalty to their father. By the time Trump Jr. joined the family company in 2001, he sounded very much like his dad: brash, confident, a son of a wealthy man who nonetheless came off like a street fighter.

For the Trumps, generation after generation, the family is the business, and the business is the family.

Once the kids accepted the terms of their relationship with their father, he became their booster — and he began to praise them in familiar terms. He loves to quote people he met on the campaign trail who told him how great his children are. He seems especially impressed that even people who said they would never vote for him told him he did something right in bringing them up.

“Children of narcissists are often high achievers because they live in fear that their parent will cut them off for a while if they fail to reflect him,” Golomb said. “It’s a very isolating way of being raised. They know exactly what will upset him, and they behave to protect him. They can’t become autonomous.”

People who study narcissism say such parents often demand unquestioning acceptance and threaten their children with rejection if they seem disobedient. But in some families headed by narcissists, it’s little more than a threat, because the adult children have learned their roles so well. They labor as a matter of course to stay in their parent’s good graces.

This past week, when Trump Jr. went on TV to defend himself and his father, the president hardly needed to mount a vigorous argument on behalf of his oldest. His next son did it for him. Eric Trump tweeted: “This is the EXACT reason they viciously attack our family! They can’t stand that we are extremely close and will ALWAYS support each other.”

marc.fisher@washpost.com

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