Prompted by President Donald Trump, Kirstjen Nielsen, 47, resigned as Secretary of Homeland Security on Sunday, April 7. Trump’s cabinet of 19 people apart from himself will now have a total of three women serving, the lowest number since the presidency of George H.W. Bush.

Famous for her strong support of the controversial separation of the “zero tolerance” policy that led to the separation of thousands of immigrant children and their parents, Nielsen is a conservative who has primarily been supportive of Trump’s immigration agenda.

Nielsen faced public controversy herself when two Guatemalan immigrant children after being brought into government custody in December. She denied responsibility for their deaths, which resulted from improper medical care.

Despite border crime rates being comparatively low to those of the 1980s to mid-2000s, Nielsen continuously declared there to be a threatening “crisis” around “crime coming across the border.” During Nielsen’s tenure as Secretary, legislation was passed that forced people seeking asylum to the United States to continue to live in Mexico as their cases are reviewed rather than waiting in the States.

While Nielsen has always defended Trump’s immigration policies, the public predicted Nielsen’s resignation for the past many months as the President has continuously shown aversion toward her.  Trump “was known to belittle Nielsen and berate her in Cabinet meetings,” according to the Los Angeles Times.

After Trump consulted with Nielsen in a meeting designated to talk about immigration, he used Twitter to declare that head of U.S. Customs and Border Protection agency Kevin McAleenan would replace her as Secretary of Homeland Security. McAleenan is in support of Trump’s efforts to install a physical barrier at the border. It is clear that the President wanted a stronger conservative in regards to immigration policies.

Discrepancies between the President and Nielsen’s department about opinions on immigration policy recently showed when Trump wanted to close the southern border. Stating that the United States is at “full” capacity, the President strongly condemned illegal immigration.

Nielsen’s department worried about the economic losses that would result from such a decision. Trump later stated that he would most likely not choose to fully close the border unless he deems it necessary.

Twenty-seven officials in the Trump administration have resigned since the beginning of the President’s term. McAleenan has been the acting secretary since Wednesday. He will serve for the “short term” according to the White House until a new secretary is officially nominated.