Michelle Obama walks along a White House colonnade with her special assistant, Kristen Jarvis, in January 2012. Jarvis is leaving the White House after seven years by the first lady’s side. (Chuck Kennedy/White House)

She was Michelle Obama’s intermediary, her message-passer, her play-date arranger, her mentee, her purse, her occasional workout buddy, her escort, her surrogate little sister, her scheduler, her coin collector, her human briefing book, her travel concierge and her constant car companion.

But you’ve probably never heard of Kristen Jarvis. Discreet and loyal, Jarvis spent the past seven years by Obama’s side. She ended her long run on the first lady’s staff this month after deciding it was time to start a new chapter.

It was a difficult decision. Jarvis, 34, entered the inner orbit of the East Wing by embodying the kind of deep, personal commitment the Obamas value. As an all-purpose personal aide, her role was roughly comparable to the job held by Reggie Love, the president’s longtime “body man.” But while Love, a charismatic former Duke University basketball player, published a memoir after his four-year White House stint, it was not until Jarvis prepared to leave the first family’s employ that she was willing to reflect publicly on her time there.

Even then, she was careful. Speaking to a reporter at a Starbucks two blocks from the White House, Jarvis brought along a member of the first lady’s communications team and shared only the most positive aspects of her experience. Michelle Obama has a reputation as being a perfectionist, but Jarvis recalled the first lady as perfectly calm during a recent minor catastrophe, when her teleprompter went missing just before a speech in New York.

“Honestly for her, what you see is what you get,” Jarvis said, adding that the first lady gave the speech from her notes. “She just really instills the confidence in you.”

Her relationship with the family began in 2005 when she joined Barack Obama’s new Senate office. Jarvis later took traveling positions during his presidential campaign, uprooting her life to move to Las Vegas for a while before joining Michelle Obama’s then-two-person campaign staff in 2008. After the election, it was Jarvis’s job to accompany the new first lady wherever she went.

The bubbly and disarming aide carried her boss’s Sharpies, tissues and hand sanitizer. She made calls to Marian Robinson, Michelle Obama’s mother, to coordinate care for Malia and Sasha Obama. She became the linchpin connecting the first lady’s extended network — friends, former co-workers, parents of the girls’ friends and her husband’s campaign headquarters.

“When people give up their life and move for a cause, there’s an extra amount of commitment that is not lost on the principals,” said Melissa Winter, the first lady’s deputy chief of staff. “The loyalty gave an extra layer of appreciation from the first lady. ”

The bond between Obama and Jarvis, forged over thousands of hours of car and plane travel, is described by some colleagues as a sisterlike relationship, by others as a mother-daughter dynamic. Raised in suburban Columbia, Md., Jarvis suffered early personal losses — both of her parents and a brother died before she was 30 — and she came to value family above all else.

“The first lady was able to fill unintentionally some areas of Kristen’s life that she was missing growing up,” Winter said.

“We’re just always together,” Jarvis said. “Whether it’s talking about work, talking about the girls, my personal life, to brief her for an event, we’re always talking.” Or they listened to music — Beyoncé and Stevie Wonder were favorites — or just sat in comfortable silence.

Jarvis, right, accompanies Sasha and Malia Obama as they prepare to board Air Force One at the Cape Cod Coast Guard Air Station after a family vacation on Martha’s Vineyard in August 2009. (Jason Reed/Reuters)

When the Obamas were overnight guests at Buckingham Palace in 2011, Jarvis was the only staff member to stay in the British royal residence, in a room about 200 feet from the first couple.

But she parted ways with the first lady when it came to fitness training. The young aide accompanied Obama to Solidcore workout classes but found them too strenuous. “She can have that,” Jarvis said, laughing.

Young staff members came to view Jarvis as a sounding board to vet their ideas before pushing them up to the first lady or her chief of staff. “What’s your gut on this?” they would ask her. Her instincts became powerful assets.

“She’s a critical link between the personal and the professional for the first lady,” said Joshua DuBois, who formerly led the president’s faith office and is a friend of Jarvis’s from their days on his Senate staff. “She does her job in a way that the first lady and president are comfortable with — in a way that feels like home.”

The job of body man — or woman, in this case — was a somewhat mysterious one until the media-friendly Love managed to convey its peculiar skill set. Love, who left the White House to get a Wharton School MBA and is now working in finance, wrote in his memoir, released in February, that he served as the president’s “DJ, his Kindle, his travel agent, his valet, his daughters’ basketball coach, his messenger, his punching bag, his alarm clock, his vending machine, his chief of stuff, his note passer, his spades partner, his party planner, his workout partner, his caterer, his small forward, his buffer, his gatekeeper, his surrogate son, and ultimately, improbably, luckily, his friend.”

Same for Jarvis, although “she was better than me,” Love insists. The first lady’s “needs and her challenges are similar but also very different from working for the president. You didn’t have to worry about hair and makeup and attire changes nearly as much.”

During the 2008 campaign, Jarvis carried a list of reputable black hair salons to ensure her boss had that essential base covered wherever they traveled. But she first distinguished herself while working rope lines with Obama. She always stayed less than a step away — in case her boss needed anything — but also charmed the crowd, greeting voters and setting a certain tone for their encounter with the candidate’s wife.

Later, Jarvis was deployed in the White House to represent Obama in lower-level staff meetings and managed the teams dealing with her travel logistics. She is described as firm but friendly when it comes to delivering the first lady’s messages.

“She’s smart and she’s not too harsh, even when she’s direct,” Love said. “She has a great way of just making people feel good about the good comments and the bad comments.”

Jarvis helps the first lady go over a speech before going onstage for a rally at the Strand Theatre in Dorchester, Mass., in October. (Lawrence Jackson/White House)

In recent months, Jarvis realized that she had gotten perhaps too comfortable in her demanding job. A theater major at Atlanta’s Spelman College, she had not begun her career with any strong interest in politics — it was the Obamas who excited her. So as attention began to shift to the 2016 campaign, she decided it was time to move on from the theatrics of Washington.

She discussed her feelings with her boss — they discuss everything — and the first lady “told me not to leave until I found the right fit,” Jarvis said. “She has been a mentor throughout this entire process.”

After each job interview, the first lady e-mailed or texted her to see how it went. Jarvis recently accepted a position at the Ford Foundation in New York, where she will be chief of staff to the foundation’s president, Darren Walker. (Jarvis’s boyfriend also lives in the area.)

“I was with Gayle King last week” — the morning network TV anchor, who is close to the Obamas — “and Gayle ran up to me and said, ‘Do you know you’re hiring the most amazing woman as your chief of staff?’ ” Walker said.

Remaining in the White House orbit is no sure thing for even the closest aides after they leave the job. Recent East Wing veterans have departed for positions at a range of institutions, including the Center for American Progress, National Geographic and the California tech company Square.

But Jarvis says she thinks that she and the first lady will stay close, even when she is not physically present. On her last trip on Air Force One, Jarvis accompanied the Obamas to the civil rights anniversary commemorations in Selma, Ala., last month. It was another special moment for a young black woman traveling with the first black first lady, and Jarvis felt nostalgic.

“It was so powerful. It felt like [both] the message of 2008 and how far we’ve come as a people,” she said.

And when the president’s plane landed back at Joint Base Andrews, the first lady invited Jarvis to exit at the front of the plane with the family. “As we walked down the steps, FLOTUS was holding my hand,” Jarvis said softly.