The First Lady wore the $39 khaki green Zara jacket upon arrival at Andrews Air Force Base in Maryland.
Donald Trump defended his wife, saying the reference was her response to the "Fake News Media".
Melania Trump was on her way to visit the detained children and families at the U.S. -Mexico border.
The controversy was surprising because Melania Trump, a former fashion model, is particularly attuned to visuals, including her sartorial choices.
For weeks, Trump had insisted he was bound by law to split children from their parents and that only Congress could resolve the problem - before he radically shifted gears.
Justice Department lawyers had been working to find a legal workaround for a previous class-action settlement that set policies for the treatment and release of unaccompanied children who are caught at the border. "Be kind and nice to each other, OK", she said as she left one classroom at Upbring New Hope Children's Center and headed for another.
Two List A records on the same day
Roy hooked a short delivery for four over midwicket and next ball, when Stanlake, again dropped short, he hooked him for six. Jhye Richardson took three for 92 in 10 overs while medium-pacer Andrew Tye's nine wicketless overs cost 100 runs.
On Twitter, Grisham continued to lament that the brushfire caused by the jacket had stepped on her message. "We don't like to see families separated".
"Now that an EO has been signed ending family separation at the border, it is time to focus on swiftly and safely reuniting the families that have been separated", the president's daughter and West Wing adviser tweeted. Melania has learned how dishonest they are, and she truly no longer cares! "It's a basic rule of thumb that if you don't want to make your clothing the focus of the story, then choose what you wear carefully so that it's not", she said.
But Trump's fashion has often played a leading role during her tenure as first lady. Some of the young people were children taken from their parents at the US border with Mexico.
Although it's unlikely that Trump was sending a deliberate message with her wardrobe choice, the optics are still bad, especially after weeks of the president passing the buck to Democrats to pass legislation ending his own policy.
President Trump said the first lady and daughter Ivanka played a big role in his decision to end the practice of separating migrant children from their parents. It is holding 55 of the thousands of children under USA government supervision.
The First Lady first commented on the issue on Sunday.
Mrs. Trump asked her staff on Tuesday to plan a trip as soon as possible - before President Trump signed the executive order, although Grisham wasn't sure if Mrs. Trump knew that the order was coming.
First lady Melania Trump greets police officers before boarding a plane at McAllen Miller International Airport in McAllen, Texas.