The zero-tolerance policy calls for the criminal prosecution of anyone caught crossing the border illegally.
That discrepancy in numbers is one of several disagreements both sides of the suit, the Justice Department and the ACLU, pledged to discuss later Monday.
Trump has for years railed against catch and release, blaming it for crimes and violence committed by unauthorized immigrants during the administration of President Barack Obama.
With no other apparent plans in motion for how to receive the waves of migrants fleeing Central America, the Trump administration appears to have turned to the very same practice the president has blamed for the status quo. I thought children were supposed to be a priority here in the United States'.
Some parents who were already deported may choose not to have their child sent to them, in some cases because the child has other family in the US or can pursue asylum or other relief.
Those separations occurred between early May and June 20 when Trump signed an executive order halting them.
In Grand Rapids, Mich., two boys and a girl who had been in temporary foster care were reunited with their Honduran fathers at a U.S. Immigration and Customs Enforcement center about three months after they were split up.
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Chris is expected to create large swells along the east coast, which can result in life-threatening surf and rip currents. A hurricane across the Atlantic may "influence" Britain's hot weather possibly bringing wind and rain next week.
Additionally, according to the lawyers, 20 children were eligible for reunification but would not be reunified by the July 10 deadline "due to legitimate logistical impediments that render timely compliance impossible or excusable".
Such testing, they said, is usually reserved for circumstances in which there are questions about the relationship between the parent and child.
"It is our hope it does not take until July 26", she said.
The administration is expected to appeal her decision. She wears an ankle bracelet, pending the outcome of her civil case.
Also, on Monday, a federal judge in Los Angeles emphatically rejected the Trump administration's efforts to detain immigrant families for an extended period. "Don't come to our country illegally", he said.
The separations - which also involve "under 3,000" older children - have sparked global outrage and considerable confusion.
The dueling statements come amid continued uncertainty over the number of young children who were separated and placed in federal custody during the implementation of Trump's "zero-tolerance" immigration policy.
President Trump makes his United Kingdom debut
It pointed to polling a year ago showing up to two million people could take part in anti-Trump actions. The organisers behind the blimp however, said they were just "poking fun" and "hope Trump sees it".
Another 2,000 to 3,000 migrant children ages five to 17 must be reunited by 26 July, a U.S. judge has ordered. But their priority is to see that families are reunited "in a manner that ensures the safety of the child"-which can take time".
"These are firm deadlines".
The ACLU did not request a specific amount of money, but said the government should be forced to foot the bill.
McConaghy also said that the USA attorney has been pressing the government to reunite J.S.R. and V.F.B. with their parents before the court-ordered deadline.
HHS has previously said there are "under 3,000" such children. They said an additional 17 could also join their parents if DNA results arrived and a criminal background check on a parent was completed.
On Tuesday morning, staff members at a private firm that has been detaining numerous youngest children "made sure every backpack was full and every child got a hug and a goodbye", Southwest Key CEO Juan Sanchez said. Gen. Jeff Sessions said in a joint statement. If those parents were able to prove a familial bond with their child using a birth certificate or official documentation, they argued, there should be no hold-up in the reunification process. He declined to provide details about every case, but said one adult was convicted of child cruelty and narcotics charges. But as government employees would soon realize, they had their work cut out for them.
Ever Reyes Mejia's 3-year-old son smiles at him while being buckled into a vehicle seat. His child had stopped talking soon after being taken into government custody.
Federal Bureau of Investigation agent says his 'blunt' criticism of Trump never impacted his work
But the report said it found no evidence of political bias in the FBI's decision to not pursue criminal charges against Clinton. To recap, Strzok was removed from the Mueller investigation and harshly criticized by an inspector general.
"I feel like he's still in shell shock", said Valdes, their lawyer.