Sandra Ortiz hugged her son Bryan for the first time in nearly four years on Tuesday. The reunion came at the very same port of entry, San Ysidro, where she was deported and separated from her son.

Later that night, Mabel, a mother from Honduras surprised her sons, Mino and Erick, at a family gathering and locked them in a tearful group hug for the first time in over three years.

These families are among the first to be reunited by organizations working with the Biden administration’s Family Reunification Taskforce. They’re also two of the thousands of families that were separated under former President Donald Trump‘s “zero-tolerance” policy that was aimed at deterring illegal immigration.

“It feels like a dream. I was in the car – like this is finally happening. I’m really going to be reunified with her after all this time,” said Bryan.

His mom was apprehended at the border as they fled cartel violence in Mexico. Bryan was initially placed in a government facility, but has since been living with older siblings in California.

In many cases, organizations like Al Otro Lado and Immigrant Defenders Law Center have been working for years to locate parents throughout Mexico and Central America. The Biden White House says the Trump administration left them little to no information about many of the families.

Four families are set to be reunited this week with more expected in the following weeks. Advocates have been working with the Biden administration to grant parents a temporary humanitarian protection, but questions still remain if they will be granted permanent status.

Mabel, whose last name is being withheld for privacy, spent two years in Immigrations and Customs Enforcement detention before she was deported back to Honduras, the very country she fled because of violence. Las Americas Immigrant Advocacy Center helped reunite her with her sons, who have been living with their grandmother in Philadelphia since they were separated.

“I love you,” she told her sons as relatives surrounded them crying and embracing one another.

As these reunions start to trickle in slowly, the daunting challenge of reuniting the rest of the families that were torn away at the border looms over the advocates who search for them. So far the Biden administration has identified more than 1,000 families that remain separated.