WASHINGTON • In 2000, Ms Melania Knauss, a Slovenian model dating businessman Donald Trump, began petitioning the government for the right to permanently reside in the United States under a programme reserved for people with "extraordinary ability".
Ms Knauss' credentials included runway shows in Europe, a Camel cigarette billboard ad in Times Square and - in her biggest job at the time - a spot in the swimsuit edition of Sports Illustrated.
In March 2001, she was granted a green card in the elite EB-1 programme designed for renowned academic researchers, multinational business executives or those in other fields, such as Olympic athletes and Oscar-winning actors, who demonstrated "sustained national and international acclaim".
"We called it the Einstein visa," said Mr Bruce Morrison, who was chairman of the House sub-committee that wrote the Immigration Act of 1990 defining EB-1.
The year Ms Knauss - now First Lady Melania Trump - got her legal residency, only five people from Slovenia received green cards under the EB-1 programme. Over a million green cards were issued in 2001, but just 3,376 were issued to those with "extraordinary ability".
Mrs Trump's ability to secure her green card not only set her on the path to US citizenship, but also enabled her to sponsor the legal residency of her parents, who are now close to obtaining their citizenship.
President Trump has proposed ending the sponsorship of relatives, slamming it as "chain migration".
"CHAIN MIGRATION must end now! Some people come in, and they bring their whole family with them, who can be truly evil. NOT ACCEPTABLE!" he tweeted in November last year.
Immigration experts said the President's efforts to restrict legal immigration put the spotlight on lingering questions about how the First Lady and her family members obtained residency in the US.
Mr Michael Wildes, an attorney for Mrs Trump, said she "was more than amply qualified and solidly eligible". But he declined to discuss the qualifications that she cited in her petition for residency.
The process of deciding who meets the "extraordinary ability" standard is subjective, said Ms Sarah Pierce, an immigration expert at the Migration Policy Institute, a Washington-based think-tank.
But it is generally thought that only the top 2 per cent of people in their field would qualify, she said, adding that the "quintessential award you want to put on the application is a Nobel Prize".