And just like that, without any further pomp or circumstance, Washington officially got its first lady.
"Looking forward to the memories we'll make in our new home! #Movingday," she posted on social media alongside an image from what appeared to be a dining room table with a window overlooking the Washington Monument.
Nearly five months into the administration, the Trumps are reunited under one roof again, following the first lady's unprecedented choice to minimize disruption for their son as he completed the school year in New York.
Now, she will focus on settling in to both her new home at the White House and to her role as America's first lady, which she will be able to embrace fully from Washington.
The extremely family-oriented Melania Trump's main priority in the immediate future is settling in son Barron. School's out for summer for the 11-year-old, who walked into his new home with the ubiquitous fidget spinner Sunday evening. He will attend St. Andrews Episcopal School in Potomac, Maryland,
Her parents, Amalija and Viktor Knavs, also arrived in Washington from Marine One on Sunday. While they won't be living in the White House full-time, they have previously split their time between the United States and their native Slovenia and will continue to spend time with their daughter and grandson.
Defining a platform
Melania Trump has already taken steps toward defining her platform, identifying women's empowerment and access to education for women and girls as key priorities for her East Wing.
Trump has also subtly signaled other priorities -- she has now made six separate visits to children's hospitals, and in early April, she visited a local shelter for abused women and children in South Florida.
She's assembled a team of staff, including chief of staff Lindsay Reynolds, social secretary Rickie Niceta and communications director Stephanie Grisham, to help her formally roll out what will ultimately become her legacy as first lady.
It took Michelle Obama a year to announce her "Let's Move" initiative, and Laura Bush held events for her "Ready to Read, Ready to Learn" initiative during the summer of her husband's first term.
"We look forward to unveiling initiatives in the coming weeks," Grisham said Monday.
Trump's arrival in Washington will also come with raised expectations for her visibility.
"Now that she's moved into the White House, as every first lady has done since Abigail Adams -- exception being Anna Harrison -- she will be expected to be more hands on," said Kate Andersen Brower, a CNN contributor and author of "First Women: The Grace and Power of America's Modern First Ladies" and "The Residence: Inside the Private World of the White House."
Her presence and positive approval rating could be a welcome distraction for a White House embroiled in controversy as the Russia investigation shows no signs of slowing down.
The President acknowledged his wife's star power at a Mother's Day event in the East Room.
"She has become so popular, it's true. It's true. In fact, I'm going to have to ask her how are you doing this, but our first lady, they had a poll that came out, she went through it like a rocketship. I said, 'How do you do this?' And that's only because people have really gotten to know her," Trump said, calling his wife an "incredible woman."
Trump has eased her way into the role, performing the traditional first lady duty of America's official hostess; initially traveling to Washington rarely, but more frequently in recent months. She's participated in key events, hosting the 179th annual White House Easter Egg Roll
and welcoming governors and spouses at the formal Governors Ball.
And she was by her husband's side throughout the inaugural festivities; she watched as he gave an address to a joint session of Congress; she joined him to award a Purple Heart at Walter Reed; and she was on the world's stage as he traveled in the Middle East and Europe on his first foreign trip
, receiving widespread praise.
She will continue to welcome world leaders and their spouses to the White House, sharing carefully curated spots as she did with Sara Netanyahu, with whom she toured the National Museum of African American History and Culture, and Queen Rania of Jordan, with whom she visited a girls' public charter school.
Her predecessor, Michelle Obama, ventured into Washington often, hitting up SoulCycle classes, dining out at up and coming establishments, and once even going shopping at a local Target. Trump, who is famously private, isn't as likely to leave the White House grounds quite as often. Her husband's only meal outside 1600 Pennsylvania Avenue so far was a ride down the road to the steak house at the Trump International DC Hotel.
Looking ahead, Trump will host the annual congressional picnic later this month with members Congress and guests. And in July, she'll accompany her husband abroad yet again, traveling to Poland and then to Germany for the G20 summit.
In the meantime, she'll adjust to her new home, city, and the more mundane aspects of daily household life with the President, who celebrates his 71st birthday on Wednesday.