|||Chris Kleponis/SIPA/NewscomChris Kleponis/SIPA/NewscomFirst Lady Melania Trump's parents officially became United States citizens this week, thanks to a part of the law that President Donald Trump has claimed several times must end.

Viktor and Amalija Knavs were sworn in at a private ceremony on Thursday. The Associated Press reports that the Knavs, who came from Slovenia, lived in the country as permanent residents prior to their ceremony. Their lawyer, Michael Wildes, has confirmed that the first lady sponsored their Green Cards.

This family-based path to America—sometimes called "chain migration"—is the most common form of immigration. Through this process, a green card holder or legal U.S. resident "may sponsor a family member for immigration." The president has repeatedly called for limiting this pathway to spouses and minor children, and he tweets frequently about its alleged evils:

NPR notes that this is not the first time someone associated with the first family has benefitted from immigration tools criticized by the president:

[Melania Trump] was paid for several modeling jobs in the U.S. before obtaining a work visa, which would be illegal under immigration law.

Her green card was granted under the elite EB-1 program, according to The Washington Post. That preferential program, popularly known as the "Einstein visa," is intended for immigrants with "extraordinary ability, [who] are an outstanding professor or researcher, or are a multinational executive or manager," according to the U.S. Customs and Immigration Services.