The sister of one of the young victims killed in the Uvalde school shooting earlier this year, as well as the city’s only pediatrician, pleaded for stricter gun laws during a congressional hearing on gun violence on Thursday.

The hearing, titled “Examining Uvalde: The Search for Bipartisan Solutions to Gun Violence”, was hosted by the House of Representatives committee on the judiciary in Washington.

At the hearing, Faith Mata, whose 10-year-old sister, Tess, was killed on 24 May during the shooting at Robb elementary school along with 18 other students and two teachers, urged lawmakers to consider tougher gun control.

“It hurts. I lost my better half,” said Mata. “We will never know how scared she was in that last classroom.”

“Are we not tired of hearing the stories of victims, hearing from victims’ families? Are we not tired of hearing yet another tragedy because of gun violence? When is enough enough?” the 21-year-old pleaded to lawmakers, recounting how her family waited for more than eight hours to discover that her younger sister had been killed.

“This debatable topic on assault rifles should not be brought up again because someone else’s child or sibling was murdered. It’s just an excuse at this point,” she said.

Uvalde’s only pediatrician, Roy Guerrero, who treated many of the slain students also testified at Thursday’s hearing.

“These kids weren’t helpless victims that day. They were spunky, intelligent, street-smart kids … But with a weapon like [the AR-15], [they] had no chance,” he said.

“You might mistakenly imagine a funeral where a child dies peacefully in a colorful coffin. But make no mistake, there’s no peace in the death of a child by a weapon of war,” he added, explaining how one of the slain children he saw at the hospital was decapitated while the other had a gunshot wound so large, he could nearly put his entire hand through their chest.

As a gun owner and a doctor, Guerrero said that he believes in the second amendment but called upon lawmakers to consider stricter control on assault rifles.

“They’re not appropriate for self-defense in a home, in the school or in the supermarket. They are and always have been designed as a military-grade killing machine,” he said.

Texas state senator Roland Gutierrez also appeared at the hearing where he condemned the police response to the shooting as one of “the worst” in American history.

According to a report from the Texas legislature, nearly 400 law enforcement agencies showed up at the scene after the shooting began but were stymied by a lack of coordination.

“Policymakers, you and I have to grapple with how much loss of life is acceptable in relation to someone’s freedom to obtain and carry a weapon that can inflict so much damage,” Gutierrez said.

“A child was dragged out of the hallway, her face was gone. Hallways and classrooms and blood like no horror movie you’ve ever seen,” he said. “Off-camera, you could hear grown men throwing up from the sight of the horror or perhaps the failure that they had caused.”

Democratic House representative Sheila Jackson Lee who chaired Thursday’s hearing called for a ban on AR-15-style weapons, saying that without it, “more people will die”.

“If we’re not going to ban them, then law enforcement must be trained to confront these weapons of war. Yes, we must train law enforcement like warriors in a battle on the combat field,” she said.

Jackson Lee also criticized Republicans for not supporting the various proposals previously put forth by Democrats to reduce gun violence such as red flag laws and raising purchasing age limits.

“I’m angry. Legislators are not supposed to be enraged. We are simply supposed to stand with stoic faces and let witnesses put their souls on the table … None of you should have to tell your stories,” she said.

Meanwhile, Republican House representative Andy Biggs pushed back against Jackson Lee, arguing that more focus needs to be directed towards the mental health of potential perpetrators.

“There hasn’t been an honest engagement and search for bipartisan solutions to gun violence, mostly because there’s only one solution for my friends across the aisle and that is to emasculate the second amendment and remove guns from legal, lawful and law-abiding citizens,” Biggs said.