Editor's Note: This article is one of 50 in a series about Trump's first two years as president.

We’re halfway through, and Ivanka Trump remains as much of a mystery as ever. Like Hillary Clinton, she has a West Wing office, and like Nancy Reagan, she has a wondering, matchless fealty to the president. She would never snatch her hand away from his, like Melania did; she would never even roll her eyes, like the Obama girls did, when they had grown tired of the turkey pardon. To Ivanka, God help us, Donald Trump is the measure of a man.

In Washington, she is known as a good dinner partner, interesting and interested, her golden beauty enhanced by candlelight and crystal. Old friends and former teachers remember her as thoughtful, hardworking, smart. Tabloid parents usually produce a tabloid child, but Ivanka has spent her life taking careful steps, and Trump could do far worse—often has done far worse—in appointing someone to a White House position. Ivanka’s no Bobby Kennedy, but neither is she Omarosa. You could spend a thousand hours in a thousand conversations with her, and she will never, ever criticize the president. Her fealty to him is absolute—as is her brothers’ and sisters’ loyalty to her. Even sibling rivalry, rich with potential in this family of three mothers and two immolating divorces, is subsumed in the family certainty: Ivanka is our treasure.

We were originally led to believe that this heightened, unbreakable bond would pay dividends, that her White House office stood as a flag planted in the ground of reason and sanity. If he proposed something loathsome, she would steal down the plushly carpeted hallway on little cat feet and steer him around to something more reasonable. But this seems not to be the case. More often, apparently, she ends up back in her office, patting her tears dry and accepting that—as ever—her dad will go his own way. There was also the notion that Ivanka would be able to conduct back-channel meetings with problematic people—for example, Cecile Richards, the former head of Planned Parenthood—whom she would charm with B-school solutions to common problems. But when Richards later said that the Trump White House was “the worst for women that I’ve seen in my lifetime,” that hope also died.

In July 2017, in Hamburg, Trump stepped away from a meeting of the Group of 20. And who slipped into his seat briefly while he was gone? Ivanka. But she did not serve a grateful nation. There was a buzz of distaste, even of anger, in the media ether, and the family had to go down the ladder from Ivanka to Don Jr. to stop it. “If the left is so ‘outraged’ about Ivanka sitting in for a few minutes,” he tweeted, “maybe they'd be happier if I sub in for a while???”  

What does she want, exactly, out of this great proximity to power, out of her years purveying older-daughter diplomacy? Oddly, given her insistence on being a thoroughly modern woman, she wants greater power for her husband, who is Trump’s very opposite: personally disciplined, loath to speak in public, willowy, deeply committed to making his one marriage last.

In the end, Ivanka stands alone among the daughters of the modern presidency. She is not Margaret Truman, forever remembered for her earnest piano playing; she’s not Tricia Nixon, stunned and silent when her dad got in trouble, or Julie Nixon, roaring out of her corner, gloves up, when it happened; nor is she Chelsea Clinton, holding on to her parents’ hands in an attempt to hold their marriage together on that long walk across the White House lawn. She is not, in other words, a supporting player; she’s some kind of principal, but beyond that, we don’t know much. Ivanka is a mystery, less powerful than she seemed at first, but still firmly wedged in there at the very center of whatever is going on in our strange, unpredictable, and increasingly dangerous White House.

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