"They're willing to risk harm to a child being traumatized, separated from a parent and sitting in federal detention by themselves, in order to reach a larger policy goal of deterrence", said Jennifer Podkul, director of policy at Kids in Need of Defence, which represents children in immigration court.
Jeff Flake of Arizona sent a letter to Homeland Security requesting additional information about the separation of children at the border, citing cases of children being separated from their parents who sought asylum at ports of entry.
United States first lady Melania Trump has spoken out about the thousands of migrant children separated from their parents by American authorities at the country's border with Mexico.
'Democrats can fix their forced family breakup at the Border by working with Republicans on new legislation, for a change! Department of Homeland Security officials said that at least 2,000 children have been separated from their parents since it began implementing the policy in late April.
Mrs Trump's spokeswoman Stephanie Grisham says the first lady believes "we need to be a country that follows all laws", but also one "that governs with heart".
The president has falsely blamed Democrats for the situation, saying that he was simply enforcing a law that they had written.
On Friday, Trump listed what he wants to be included in an immigration bill, again blaming Democrats for their "horrible and cruel legislative agenda".
The policy has divided Republicans, with its defenders pointing out that children are routinely taken from parents accused of crimes.
But other members of the administration who have had a central role in immigration policy embraced the decision to separate families. Ted Cruz, said the process of separating families is 'inhumane'. More adults were being jailed as a result, which led to their children being separated from them. "I...[condemn] the continued use of family separation at the U.S./Mexico border..." "I will tell you that nobody likes this policy". "False. False. A bipartisan 2008 law merely gave the government flexibility in processing border-crossing immigrants".
The handout recommends that parents call ICE, call the ORR Parent Hotline, or email the two organizations to locate their children.
Trump made his remarks in his weekly address and as House lawmakers are negotiating legislation that would limit some forms of migration, fund border security and would also grant protected status to some illegal immigrants brought to the country as children.
Inside the Trump administration, current and former officials say, there is considerable unease about the policy, which is regarded by some charged with carrying it out as unfeasible in practice and questionable morally.
"From the experience of previous administrations, it does not act as a deterrent to use children in this fashion", she said. They are fleeing violence and persecution, and he doesn't see that changing even if the government deports parents. "I do remember looking at each other like, 'We're not going to do this, are we?' We spent five minutes thinking it through and concluded that it was a bad idea".