“Be hopeful.”

That’s the message Sirley Silveira Paixao has for fellow asylum-seeking mothers who were separated from their children at the U.S-Mexico border in recent months.

On Thursday, a federal judge in Chicago ordered the federal government to release Paixao’s son, Diego, to her custody after spending more than a month apart.

“We expected today’s results given the judge’s previous ruling,” Paixao said through a translator at a press conference Thursday morning after the hearing. “I’m excited to have him back and he’s not going to leave my side ever again.”

Lawyers for the mom asked U.S. District Judge Manish S. Shah to order the boy freed, and for the second time in such a case, Shah agreed. The judge made a similar ruling last month in the case of a 9-year-old Brazilian boy who had been separated from his mother, Lidia Souza, at the border on May 30.

RELATED: Mom and 9-year-old son reunited after pair separated at US border

Upon apprehension at the border, Paixao and her son were placed in a federal detention facility in El Paso, Texas, on May 22.

Two days later, authorities shipped Diego to a facility in Chicago run by Heartland Alliance, a non-profit contracted to house “unaccompanied” refugee and immigrant minors by the Office of Refugee Resettlement under the Department of Health and Human Services.

The mother and child were separated from each other as part of President Donald Trump’s “zero tolerance policy,” which aims to criminally prosecute all persons caught attempting to illegally cross the U.S.-Mexico border, including parents traveling with their children seeking asylum. A consent decree reached in 1997 forbids the government to hold children in detention centers for more than 20 days.

Paixao was released from federal custody on June 13 and is living with a family friend near Boston.

Paixao’s son was held at a Heartland facility since May 24, according to court records. Paixao was not able to communicate with her son until June 14. During that first phone call, Paixao says she “cried so heavily that her son was unable to recognize her voice.”

On Monday, Paixao filed a lawsuit in the Northern District of Illinois calling for Diego’s immediate release. Her lawyers contended that the government could not hold her son as an unaccompanied minor given that he has a fit parent who entered the country with him.

Judge Shah agreed and filed a motion to immediately release Diego to Paixao’s custody. Lawyers representing Heartland Alliance, which was named in the lawsuit, were not present at Monday’s hearing.

RELATED: Protesters march in Pilsen as growing movement to abolish ICE hits Chicago

Since October, federal authorities have separated roughly 3,500 children from their parents at the border.

On June 27, U.S. District Court Judge Dana Sabraw in California ordered federal officials to stop detaining parents apart from their children except if the parent is unfit or if the parent declines reunification. Sabraw also ordered the government to reunify all parents with their children who are under the age of 5 within 14 days and reunify all parents with their minor children age 5 and older within 30 days.

On Thursday, Health and Human Services Secretary Alex Azar said the agency “has identified under 3,000 children in total” in its custody who were separated from their parents at the border, “including approximately 100 children under the age of 5.”

It is unclear whether the government will meet the court-ordered deadline for reunification.

Hundreds of thousands of people gathered in cities and towns across the country last weekend in protest of the Trump administration’s zero-tolerance policy.

Paixao was a featured speaker at the march and rally in Boston. There she spoke of the pain of having her son stripped from her.

“Nothing will ever repay this,” she told WCVB through a translator. “Just give these children back to their parents. These children are suffering. We don’t even know how these children are going to come out of this facility psychologically.”