Transcript for The deadline to reunite immigrant children edging closer

this hour, them administration now arguing for extension today, after a judge ordered a deadline to reunite children under 5h theiparents. The children who had been separated. The trumpinn now saying they tried, they couldn't meet thedeadline. Government lawyers now saying theed more time, revealing nearly hf of the children under have still not been reunited. Some parents have beendeported already. Are they now turning to DNA to try to M some of these children, as we here's ABC's chief jus corrndent Pierre Thomas on thatront tonight. Rter: Tonighreunions like this delayed for dozens of theoungest children who were separated from their parents at the border under the president's zero tolerance policy. Today,overnment admitting it won't able T reunite all children under age 5 by tomorrowcourt-ordered deadline. Ry day that goes by W Chilen are not reunited is troubling. Reporter: 54 of T 102l see theirents tomorrow. Have already beeunited. The government arguing it needs time to come background checks and DNA testing to confirm families tie some parents can't immedia be found. 18 have been either deported or released inside the U.S. D O 3-year-old is inbo because authorities simply have no inforon about the parents. This is a child who they T even know who the parent is. Obviously we are deeply concerned about. Reporter: For months, immigration advocates have been lling for fami T reunited. And pie area Thomas with U live tonight. The judge has set a new line for theemainining children under 5? Reporter: The judge could im a new deadline for T rest of thoseery young children by tomorrow morning. As for the 54 children that will see their parentsorrow, they will be brought to I.C.E. Faties around the country to reconnect. David? Pierre, thayou. President trump facinw

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