For nearly two months, the White House held a prime piece of office real estate in the West Wing for Ivanka Trump.

The administration reserved the space, a senior official said, in case the first daughter decided to carve out a niche there. Trump didn’t regularly use the office until this week, the White House said, though she occasionally popped up in government meetings with her father and other world leaders, including Canadian Prime Minister Justin Trudeau and German Chancellor Angela Merkel.

But never before has an administration kept open a West Wing room for someone, family or otherwise, after work has begun, said Ronald Kessler, author of “Inside the White House: The Hidden Lives of the Modern Presidents and the Secrets of the World's Most Powerful Institution.” The exclusive space is simply too tight.

“Like everything else Donald does,” he said, “it’s unconventional.”

Kessler, who happens to be friends with the Trumps,  said it makes sense if you know the family: The president values Ivanka Trump’s counsel, and Trump, as she stated on Facebook in January, wanted to take time to settle into Washington and make sure her three children comfortably adapt.

“It’s a luxury they can afford themselves because they don’t need jobs,” he said. “They can pace themselves.”

As the role of government has grown, so have the numbers of top staffers, and many potential West Wing dwellers have spilled over into the next-door Eisenhower Executive Office Building.

“Offices in the West Wing were hungrily coveted,” Don Regan, Ronald Reagan’s chief of staff, noted in his book “For the Record: From Wall Street to Washington.”

“One high-ranking official, relegated to a beautiful and spacious vaulted office in the executive office building, pleaded with me with tears in his eyes for space, any space, in the west wing.”

The West Wing is a deceptively cramped building, with aides working feet from their bosses. Natural sunlight is limited, especially on the first floor. Trump's turf on the second, a former Obama aide said, is more likely to have windows and privacy.

A White House spokesman declined to comment on how the office was used before the first daughter settled in or whether others were barred from the room. It's also unclear which suite, exactly, she occupies. She’s situated on the second floor near deputy national security adviser Dina Powell, who was initially hired to advise her.

Despite her prestigious new digs, Trump will serve as an informal adviser to her father, without a paycheck or a job description. She has pledged to adhere to ethical regulations, though she’ll receive little oversight from non-relatives. This has irked some Washington insiders, who have called her rapid ascent an extreme example of nepotism.

“If Ivanka Trump were not the president’s daughter, would she be given a White House office to perform a job that has no description?” Amanda Carpenter, a former adviser to Ted Cruz, wrote this week for Cosmopolitan. “Of course not. Don’t believe me? Just try calling the White House and asking if you can have some gratis work space at 1600 Pennsylvania Ave., one of the most coveted real estate properties on the planet.”

Trump’s move is unprecedented in more ways than one. She pointed out in a statement that a president’s adult child doesn’t really have a playbook and that she has informally advised her father for most of her life, at the Trump Organization and on “The Apprentice.” (Avoiding an official title and compensation keeps her in compliance with anti-nepotism laws.)

Trump had kept her Washington plans largely under wraps.

“Will you have an office in the East Wing?” ABC’s Deborah Roberts asked her in January. “Do you have a sense of what you think you want to carve out as a role?” “Today my focus is really just moving to Washington,” the first daughter replied, “traveling around the country and listening.”

Traditionally, the first lady's office is housed within the East Wing. Melania Trump, however, has stayed in New York to keep her young son Barron's schooling consistent.

Ivanka Trump, meanwhile, stepped down from her companies in January, asserting she'd like to focus on her family. She stayed silent in February when the retailer Nordstrom dropped her clothing line and White House counselor Kellyanne Conway, who now works down the hall from her, apparently violated federal rules by advertising Ivanka Trump products.

“Go buy Ivanka’s stuff is what I would tell you,” Conway said on the talk show “Fox & Friends.” “I’m going to give a free commercial here. Go buy it today, everybody.”

She didn't comment after her father shared his thoughts on the matter, either.

“My daughter Ivanka has been treated so unfairly by @Nordstrom,” Trump tweeted Feb. 8. “She is a great person — always pushing me to do the right thing! Terrible!”

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