The executive order President Trump signed Wednesday to end his own administration's policy of forcibly separating families at the U.S. border does nothing to address the more than 2,300 children who have already been taken away from their parents since April.

What happens to them next is unclear, and it appears the U.S. government isn't certain, either.

Some children have been sent to the Philadelphia region, but it's not clear how many. City and state officials say the federal government has largely kept them in the dark.

Here's what we know:

What have federal government officials said?

Two officials from the Administration for Children and Families gave contradicting statements to CBS News, with one saying there wouldn't be special efforts to reunite children, and another official saying it was still early and "we are awaiting further guidance on the matter."

The U.S. Customs and Border Protection agency said children already in custody wouldn't be reunited with parents until after they are prosecuted.

Have federal agencies been able to keep track of children once they’ve been separated?

Poor coordination among agencies involved in the detention and processing of migrant families has often made it difficult to track separated children and parents, the New York Times has reported.

The disarray was described in the Washington Post by an assistant federal public defender in El Paso, who said his office has desperately tried to find where children have been sent — sometimes waiting on hold for nearly an hour with the Office of Refugee Resettlement — but received little information. As Erik Hanshew wrote, parents have been distraught:

I can't promise that they'll be able to speak to their children, or know their whereabouts or who is taking care of them, or whether they'll be sent back home without their kids.
Why so many unknowns? This administration appears to have no infrastructure, policy or plan in place to deal with the destruction of families seeking refuge or a new life in our country. The disarray and confusion are on full display at the detention hearings I've attended for my clients.

Is there a fear some children and parents will never be reunited?

Yes. A former ICE official recently expressed concerns about this to Jackson Proskow, the Washington bureau chief for Canada's Global News channel.

The Dallas Morning News also reported it could be months before parents and children are reunited — if they are at all.

>> READ MORE: Children separated from parents at the border are being held in Philadelphia region, but it's not clear how many

The pace at which the children's and parents' cases are resolved differs, as the Times reports:

In federal court, parents typically plead guilty to the misdemeanor offense of illegal entry. Many are then likely to accept "expedited removal" from the country, in the hope of being reunited quickly with their children. But children cannot be subject to expedited removal; they are automatically entitled to a full hearing before an immigration judge, and their cases take longer to resolve.

What has happened to parents and children once they have been separated?

As USA Today reports:

Adults arrested for illegally crossing the border are sent to federal court under the custody of the U.S. Marshals Service, then placed in a detention center, according to the Homeland Security Department. Children taken into custody when their parents are arrested … are transferred to the U.S. Department of Health and Human Services for placement in a juvenile facility or foster care if no U.S. relative can be found.

Some children have been sent to shelters and foster-care agencies in faraway states such as Pennsylvania. Fifty were sent to Pittsburgh, the Post-Gazette reported. Others have been taken to New York, Michigan, South Carolina, and Florida, CNN said.