As registration opened Monday for an estimated 500,000 spouses of U.S. citizens to gain legal status without having to first leave the country, Karen and Xavier Chavarria had nothing to celebrate. Like many others, Karen left the United States voluntarily — in her case, for Nicaragua — as the price of living in the country illegally, planning to accumulate enough time away to be able reenter and reunite with her husband, Xavier, on a path to citizenship. Joe Biden's offer of a path to citizenship without having to first leave the country for up to 10 years is one of the biggest presidential orders to ease entry for immigrants since 2012, when the Deferred Action for Childhood Arrivals program allowed temporary but renewable stays for hundreds of thousands of people who came to the United States as young children with their parents.