Every single day, hundreds of students make the journey from Mexico to the United States to attend school. Nine-year-old Julia Isabel Amparo Medina is one of these fellow students, who commutes with her brother, Oscar, from Tijuana to San Ysidro, California for class. But on Monday, March 18, the two siblings were stopped by U.S. Customs and Border Patrol (CBP) after Julia was accused of lying about her identity. 

A 9-year-old United States citizen was detained at a Southern California border checkpoint for more than 30 hours this week while the authorities said they worked to verify her identity.

Julia Isabel Amparo Medina had her passport with her. https://t.co/dvJvCvmH7Y

— Kyle Griffin (@kylegriffin1) March 24, 2019

The children are usually driven across the border by a family friend, Michelle Cardenas, but on this particular morning, the traffic was slow and they were already running late, so they decided to walk instead and take an Uber the rest of the way.

Julia and Oscar approached the U.S.-Mexico border at 4 A.M. with two other children, and presented their U.S. passport cards. CBP officers then accused la niña of pretending to be her cousin Melanie, stating that the photograph on her passport card didn’t resemble the person they were seeing in front of them. The officers went onto involve 14-year-old Oscar, accusing him of smuggling, among other offenses.

Not understanding what crimes he was accused of and only wanting to see his sister, Oscar signed a document confirming that Julia had indeed lied about her identity to try to enter the U.S.

“That is not true,” said Thelma Galaxia, the mother of Julia and Oscar. “She is my daughter. He was told that he would be taken to jail and they were going to charge him for human trafficking and sex trafficking.”

When Galaxia was informed about the situation, she involved the Mexican consulate, and 36 hours later, Julia was released.

“I was scared. I was sad because I didn’t have my mom or my brother. I was completely by myself,” the fourth-grader said.

It’s no surprise CBP defended their decision the following day, stating they were simply performing their due diligence. “It’s important that CBP officials positively confirm the identity of a child travelling without a parent or legal guardian,” CBP Public Affairs officer Jackie Wasiluk told NBC 7.

U.S. Customs and Border Protection officials are defending the decision to detain a 9-year-old girl who officers said provided inconsistent information during her inspection. https://t.co/DrN3nCfSR2

— #NBC7 San Diego (@nbcsandiego) March 21, 2019

In regards to the methods used to verify a person’s identity (y por qué it took them 36 hours!), no details were given.

“Some specifics of our techniques for determining the true identity of a person crossing the border are law enforcement sensitive information,” Wasiluk added. “In addition, some details of this case are restricted from release due to privacy concerns.”

Watch the emotional family reunion below:

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