When Patricia's 15-year-old son and 9-year-old daughter arrived at San Francisco International Airport, it seemed to take the younger child a second to recognize her mother — she was a toddler when Patricia left Guatemala for the U.S., and the family had been separated for almost eight years.

Their reunion in August was so joyful, according to Amir Freund, the Kirkland & Ellis LLP partner who guided Patricia through her five-year fight to unify her family, that it contained no hint of the tragedy that had led her to his office many years before.

"As a mother, the hardest thing to ever do was to leave my children behind," Patricia, who asked Law360 not to use her last name and the names of her children to protect their privacy, said through an interpreter last month.

Patricia said she left Guatemala to find a way to support her family, but the job she found in the U.S. was a source of danger: She and two coworkers were sexually assaulted by her manager.

"It has a psychological effect, and as a woman you are marked for the rest of your life," she said regarding the trauma she experienced.

But out of that event, a new possibility for reuniting Patricia's family presented itself: the U visa, a path to residency for unauthorized immigrants who are the victims of serious crimes here.

Patricia's road had not been easy even before the assault. A single mother, she set off for the U.S. border in 2012 in search of a way out of the poverty that surrounded her family in Guatemala. After two weeks of traveling through the mountains, she arrived at the border crossing in Reynosa, Mexico, where she landed in immigration detention.

She was deemed inadmissible but was released from detention on an order of supervision after relatives on the West Coast vouched for her.

In California, Patricia found work with a cleaning company, but that's when things took a turn for the nightmarish. She and two other women found that their paychecks didn't reflect the hours they worked, and worse, their manager harassed and assaulted each of them.

When they complained to the company owners, they were fired.

Hoping to recover some of the pay they were still owed after their ordeal, the women reached out to Unidos US, formerly the National Council of La Raza, a Latino civil rights and advocacy group. Once the women explained what they had been through, the organization encouraged them to press charges.

Through its partnership with Kirkland's pro bono program, Unidos connected Patricia with Freund, and the pair set out to rectify her situation.

As an unauthorized immigrant who was the victim of a violent crime, Patricia was eligible to apply for a U visa. Recipients gain a three-year visa, work authorization, the chance to apply for permanent residency and, crucially for Patricia, the ability to sponsor immediate relatives to come to the U.S. But there was a catch.

Congress created the U visa program in 2000 with the passage of the Victims of Trafficking and Violence Protection Act. The aim of the program is to assist law enforcement in investigating crimes, "while also protecting victims of crimes who have suffered substantial mental or physical abuse," according to U.S. Citizenship and Immigration Services.

In order to qualify, victims must cooperate with the police or other agencies, a requirement that can be daunting to people who have spent months or years keeping a low profile for fear of deportation.

But Patricia didn't hesitate. Motivated by the prospect of reuniting with her children, she "went above and beyond" assembling documents related to her case and her application for humanitarian parole for her children, Freund said.

Patricia's courage in starting over in a foreign country resonated with Freund, who is originally from Israel. One of the first challenges the pair overcame in working together was a language barrier.

"It's hard to work with a client that doesn't speak English. It's hard to communicate," Freund told Law360. "So the way we communicate is we text each other, and I use Google translator to translate from Spanish to English."

In April 2015 they filed her application. And then they waited.

With an annual cap of 10,000 U visas, USCIS says it has received more applications than it can grant each year since 2010.

As of Oct. 8, USCIS was processing U visa applications submitted on Jan. 4, 2016, a wait time of more than 4½ years.

Alma Rosa Nieto, a California-based immigration attorney whose firm has handled hundreds of U visa applications, has watched the waiting period for U visa approval grow from months to years as more and more people have started vying for the limited number of visas, leaving applicants like Patricia in a precarious position.

"Until you get approved with a U, you are undocumented," Nieto told Law360. Until USCIS makes a decision on a crime victim's application, they are still at risk of deportation.

After processing, successful applications are added to a waiting list until a visa becomes available. USCIS does not publish information about how long applicants spend on the waiting list.

After just over three years, Patricia's application was approved in July 2018. But with no guarantee when a visa would become available for her, she and Freund decided to apply for humanitarian parole in order to bring her children to the U.S.

As luck would have it, Patricia's U visa was finally granted on April 1, one week before her humanitarian parole application was approved and almost precisely five years after she filed the application. She was thrilled, but now a new problem had arisen: COVID-19.

"The challenge was that everything was shut down in Guatemala, including the U.S. Embassy," Freund said.

After eight years of struggle, the family had all the authorization they needed to reunite in the U.S., but no way to complete the final steps to bring the children over, which involved collecting their fingerprints, a process that could only be done at the embassy.

Freund and Patricia made one last push. All told, Freund invested 117 pro bono hours on the case over the years, while Patricia and her mother worked diligently gathering documents and making the necessary phone calls in Spanish.

Finally, the embassy agreed to open up to process the children's humanitarian parole on an emergency basis.

With masks on and presents to celebrate their arrival, Patricia, her husband, her youngest child, who was born in the U.S., and Freund were all waiting to greet her son, now a teenager, and her preteen daughter when they touched down in the U.S. on Aug. 7.

The initial shyness of their long separation dissolved into hugs and tears, Freund said.

"At the beginning I was trying to maintain physical distancing, but after seeing all that, I had to hug Patricia and shake hands with her kids to welcome them and tell them that I'm very excited to see them and that their mother actually worked very, very hard to get them here, so they should be proud of her," he said.

The weeks since have been dedicated making up for lost time, according to Patricia.

"My heart was broken, but thanks to Amir and all his work it's being put back together now," she said.

--Editing by Brian Baresch.