Transcript for How will Trump's order affect separated children?

Our thanks to you. Now to the American border this morning because there are major new questions about the president's new executive order, especially when it comes to the more than 2,000 children already separated from their parents in just the last month or so reportedly sent to more than a dozen states. Is there any plan to reunite them now? How long can you now detain entire families together because of this new executive order? ABC's gio Benitez is in El Paso. What are you learning? Reporter: We don't know how long that process will take and some experts really worry this morning that some of those children may never be reunited with their families. We've seen their faces, children side by side behind metal fencing sleeping under foil blankets and heard their voices in this recording first obtained by pro publicly ka. Mommy. Daddy, daddy. Reporter: Now this morning the big question what is next for the more than 2,000 children recently separated from their parents at our nation's borders? Ruben Garcia on the front lines. He runs a shelter helping migrant families. Now we're talking about more than 2300 kids. Correct. Correct. And the parents of 2300 kids that are locked up in different places. Reporter: And we now know those in federal care include the very young, the associated press reporting that babies and small children are being housed in tender age shelters like this one in Brownsville, Texas. "The New York Times" obtaining this photo of a toddler inside of this shelter seemingly about 12 months old. ABC news was there as one young boy, 10-year-old Samuel, packed up his belongings at a Michigan home in week separated after his father after illegal will go crossing the border. He had been living with an American foster family for eight months. They asked us not to show their faces. We developed a relationship but not any expense for the trauma he's been through at all or his family. Reporter: On Wednesday our Alex Perez right there as superial got on a plane to Guatemala to meet his father who was already deported back there. At the airport Samuel seemingly stunned. A lot of love for your family in the United States. Always, always, always. Reporter: And that reunion eight months in the making. But that doesn't mean that the trauma has ended. Dr. Colleen craft says reunifications that the potential to be just as fraught as detention. It may be even difficult once they're reunited with their parents. It may take a long time for this trauma to be resolved and these children to be healed. Reporter: Experts tell us they don't know how this reunification process is going to work because no one agency actually knows where all of the parents and kids are right now and some of those parents may have already been deported just like Samuel's father. With their children back here in the U.S. In the meantime, do we know the trump administration commented how they're planning to reunite separated families? Reporter: You know, David, just moments ago we actually got information from customs and border protection. I want to read some. For those still in border patrol custody we are reuniting them with parents or legal guardians following prosecutions and they say that the families that are going to be coming now, those families will be kept together.

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