On Thursday, he said there are somewhere "under 3,000" children who were believed to have been separated, but that includes kids who may have lost parents along the journey, not just parents who were detained at the border.
This was a tall order, but Azar said officials were working expeditiously and could meet the court-mandated deadlines.
Azar said that verification process in some cases involves DNA testing.
In Friday's legal request - the government asked for more time and clarification on if their current process for confirming parentage is consistent with the court's mandate and "seeks clarification that in cases where parentage can not be confirmed quickly, HHS will not be in violation of the Court's order if reunification occurs outside of the timelines provided by the Court".
He said that order, from Obama-appointed federal Judge Dolly Gee of Central California, conflicts with a new order from Judge Dana Sabrow, a Bush 43 appointee, which demands that children be reunited with the adults they crossed the border with.
But the process that the U.S. Department of Health and Human Services has put into place to match up family members will take some time if it is to comply with existing law meant to protect children from human trafficking, the DOJ argues. "What we care about is the kids' welfare".
Trump reversed course on June 20 amid an global outcry, saying families should remain together.
Officials have said they'll comply with the judge's order, but they haven't specified what steps they'll take to do that. Before the Trump administration's "zero tolerance" policy, migrants seeking asylum under USA laws were often granted temporary release as their cases were resolved.
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I don't know if that's two or 10, or somewhere in-between. "I think everyone needs to recognise that". While it was a painful experience, it actually brought us closer .
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Khan for his part greeted news of the verdict with jubilation at a campaign rally in the Swat valley in Pakistan's northwest. Sharif's political opponents hailed the verdict, saying it was the beginning of real "accountability of thieves".
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It could be his last World Cup , but he'll remain in the heads of each football fan, each journalist, each person in the entire world forever".
"While we understand the interest in detailed breakdowns of this information, our mission has been and remains to provide every minor transferred to HHS, regardless of the circumstances, with quality and age-appropriate care and a speedy and safe release to a sponsor".
He told reporters hundreds of government employees were using DNA and other information to verify guardianship before reuniting the children with parents being held in detention. But he signaled they'd ask a judge for more time.
"The safety and security is paramount, and it is not uncommon for children to be trafficked or smuggled by those claiming to be parents", the official said.
Health and Human Services deployed more than 200 workers to review the cases of separated children.
It's been more than a week since they released a tally of how many kids from separated families remain in government custody.
In a series of tweets, Trump demanded lawmakers "pass smart, fast and reasonable Immigration Laws" now, after the House of Representatives last month rejected a broad immigration bill that had his support.
"When people, with or without children, enter our Country, they must be told to leave without our", Trump wrote.
While illegal immigrant children have dogged the government for years, dating back to the Obama administration, this latest go-around has been more pointed because some of it is a result of President Trump's get-tough policy on the border. The Justice Department lawyers also asked the court to clarify the start date for separations, as some families were separated before the official start date of the "zero tolerance" policy in May 2018.