At night, parents with young children march through the brush after crossing the Rio Grande River in the pitch black. By day, unaccompanied kids arrive at shelters, in one instance 17 of 17 testing positive for COVID-19.Driving the news: Axios accompanied a delegation of Republican lawmakers to South Texas last week — followed by a unilateral visit to El Paso — to see in real-time the challenges fueled by a border surge, the effects of actions taken by the previous administration, and the lagging response by the new one.Stay on top of the latest market trends and economic insights with Axios Markets. Subscribe for freeWhat we saw: Abandoned flotation devices litter each bank of the Rio Grande between Mission, Texas, and Reynosa, Tamaulipas, Mexico.Smugglers and U.S. border agents peer at each other across the river late at night through night-vision goggles. A bright light pinpoints a smuggler across the Rio Grande River staring back at the delegation and border agents through their own night-vision goggles. Photo: Stef Kight/Axios Just down the road, hundreds of recently arrived migrant parents and children sit in the dirt at a makeshift processing center under the Anzalduas International Bridge in McAllen, Texas. They are penned in with orange safety netting and provided Little Hug fruit barrels and water.On a hot afternoon in El Paso, migrant adults and families are marched in single file back across the bridge into Ciudad Juárez, Mexico — expelled without a chance for asylum under a Trump-era order kept in place by President Biden.Just that morning, a dozen or so single males walked in the opposite direction across the same bridge after spending two years waiting under the so-called Remain in Mexico program. A woman and young boy being expelled to Juarez, Mexico, at the end of a long line of single adults. Photo: Russell Contreras/AxiosBetween the lines: The visit illustrated the complexities of the country’s migrant crisis in heart-wrenching detail — a reality that goes far beyond the political soundbites that are driving the national conversation.In March, the U.S. experienced the highest number of border crossings in 15 years, on top of record numbers of unaccompanied minors.Congressional Democrats had known passing comprehensive immigration reform was a long shot, hoping instead to pass pathways to citizenship for Dreamers and essential workers.Republican opponents have been bolstered by the surge at the border.During the congressional trip, Republican members of the House Judiciary Committee largely spoke to law enforcement officials in South Texas, who underscored the record levels of migration in the area.They heard from overwhelmed and disgruntled border officials in the Rio Grande Valley area, and state troopers who talked about taking down drug smugglers and human traffickers.Brandon Judd, president of a large, conservative Border Patrol union, aggressively criticized President Biden's decision to end President Trump's Remain in Mexico policy — saying he would rather see policy changes than more funding.There is “zero social distancing” inside the temporary holding facility in Donna, Texas, one Rio Grande Valley border official told the members.Pods designed to hold 30 to 50 migrants during the pandemic had 10 times those numbers, according to staffers and members who briefed Axios after their tour inside. Migrant teenage boys receive their initial health screening before entering an already overcrowded Border Patrol center in Donna, Texas. Photo: Stef Kight/AxiosRep. Burgess Owens (R-Utah) described seeing a 7-year-old girl with mental disabilities who had been held for more than two weeks. "She had tears in her eyes the entire time," he told Axios.That same day, all 17 kids who arrived at the Upbring New Hope shelter tested positive for coronavirus, workers said. It's a sign of the added complications in caring for migrants during a pandemic.Each stop provided reinforcement for the talking points of some of President Trump's staunchest defenders in the House, which were repeated on Fox News and Newsmax throughout the trip."Crisis," "chaos" and "catastrophe" were the words of choice."You can't get into your capital, but anybody and everybody can get into your country," Rep. Jim Jordan (R-Ohio) said during a press conference outside the headquarters for the National Border Patrol Council.Meanwhile, interviews with House Democrats and directors of nonprofits on the front lines in El Paso revealed the human trauma inflicted by U.S. policies — and raised questions about their effectiveness.Several expressed frustration the Biden administration was caught flat-footed by rising border numbers, hasn't ended the rapid expulsion of families to Mexico, and hasn't acknowledged the severity of the situation. Families with small children prepare to board a bus at the temporary outdoor processing site under the Anzalduas International Bridge, which will take them to a local charity to help them reach their final destination. Photo: Stef Kight/Axios “I don't understand why they're not being more transparent,” Rep. Veronica Escobar (D-Texas) told Axios after being asked about the little access provided for media. Axios was not allowed inside U.S. facilities such as the Donna temporary center, ports of entry and a child migrant shelter, despite being invited to join the Republican delegation and requests directly with the Department of Homeland Security and Department of Health and Human Services.Axios was allowed in an emergency shelter in a sports complex in Ciudad Juárez run by the Mexican federal government. It opened Monday after more than a dozen other facilities in the area were beyond capacity. It already held around 170 migrants, mostly women and children.One 34-year-old Salvadoran woman walked up to a reporter with a 2-year-old on her hip.She sobbed as she described in Spanish being placed on a plane, thinking she would soon be reunited with her husband and 11-year-old daughter in Georgia — only to be told she actually was back in Mexico.She received no interview with officials and no explanation as to why she was being expelled. Mexican kids peer into Sunland Park, N.M., from the other side of the border wall. They gave Axios permission to take their photo. Photo: Stef Kight/AxiosLike this article? Get more from Axios and subscribe to Axios Markets for free.