Viktor and Amalija Knavs, Melania Trump's Slovenian-born parents, took the oath of citizenship in NY on Thursday, their lawyer confirmed.
Trump hasn't commented or tweeted about his in-laws' newfound citizenship.
Trump's plan, which Congress has resisted, would limit immigrants like his wife to sponsoring only their spouses and underage children to join them in the USA, not their parents, adult children or siblings.
A source familiar with the situation told Yahoo News that the Knavses received their green cards before Trump was elected and that they were sponsored by their daughter.
He did not specify how long it had taken the Knavs to complete the citizenship process, nor whether the 48-year-old First Lady had sponsored their permanent residency.
Mina, Gomes deals confirmed as Everton complete Barcelona raid
The Colombian has signed five-year deal with the club after moving from Barcelona for a fee of around £28million. He is a very good coach and he has achieved really good things at other clubs.
"They would appreciate their privacy and we just thank everybody for their attention for this very important dialogue we're having on immigration".
Currently, the majority of green card recipients receive them via family sponsorship. A smaller number go to immigrants based on their employment, and other categories include refugees and other special cases.
Wildes wouldn't comment on how the Knavs received their green cards or citizenship Thursday, but criticized the Trump administration's immigration policies to CNN.
The Knavses raised Mrs Trump in the rural industrial town of Sevnica while Slovenia was under Communist rule.
President Donald Trump's parents-in-law have become USA citizens in a private ceremony.
The first lady was named Melanija Knavs when she was born in Slovenia but later changed her name to Melania Knauss when she began her modeling career.