HARRISBURG (AP) — Republican U.S. Rep. Lou Barletta is backing President Donald Trump through every twist and turn of the immigration debate as he and the man he is trying to unseat, Democratic U.S. Sen. Bob Casey, split Monday on what to do instead of separating children from detained migrant parents.

Barletta and Casey both made appearances in Pennsylvania on Monday as the immigration debate roils Congress and could spur more votes this week.

If broader immigration legislation fails again, Barletta said, he would support a narrower bill potentially forthcoming from House GOP leaders to address a federal court settlement that forbids the government from keeping children and families in custody beyond 20 days. It could be similar to a bill proposed by Republican senators would require the Homeland Security Department to keep immigrant families together during legal proceedings.

“So let’s fix the parts that we can and have compassion for the children and families; nobody wants to see them separated,” Barletta told reporters after speaking at the Pennsylvania Press Club luncheon.

The four-term Barletta has backed Trump faithfully on the immigration debate, defending the policy of separating children from detained migrant parents as a deterrent, while also saying he doesn’t want to see families separated.

Casey said separating children from their families is a policy “from the pit of hell” and criticized the practice of detaining families indefinitely — even if together — as able to inflict psychological damage on children.

Instead, monitoring systems could prove effective, Casey said.

A federal pilot program using monitoring strategies that was in effect before the Trump administration ended it showed more than 90 percent of families came back for hearings, Casey said.

“I think you can have a policy that does everything that’s appropriate and effective ... and still treat children humanely, especially children that have already been traumatized for a long period of time when they get to the border,” Casey told reporters after a news conference at Philadelphia’s 30th Street Station.

Casey said he supports legislation to that effect introduced by Sen. Dianne Feinstein, D-Calif.

Casey and Barletta also have split over offering a potential pathway to citizenship to many young immigrants who arrived in the U.S. illegally as children. Barletta opposes it, while Casey supports it and voted for a wider-ranging immigration bill in 2013 that included the provision.

Barletta, the former mayor of the small Pennsylvania city of Hazleton, rose to political prominence as a foe of illegal immigration and was an early supporter of Trump, who urged him to run for Senate.

Separating children was a consequence of Trump’s zero tolerance policy and “magnified” by it, Barletta said.

“There’s nothing good that comes of illegal immigration, nothing good,” Barletta said. “Nothing good along the way, nothing good when people get there, nothing good for innocent Americans who sometimes become victims of it. And we could fix it and what does Congress do? They talk about it. We’re still talking about it.”