Fatima Dominguez spent part of her Good Friday recounting her brother’s violent death, urging nearly 2,000 fellow Chicagoans to join her in fighting gun violence.

Pausing several times to compose herself, Ms. Dominguez, who is 16, recalled how she went “numb” when she learned over the telephone in December 2016 that her 17-year-old brother, Daniel Torres, had been shot to death.

“My wounds are still fresh,” Ms. Dominguez said during a speech in front of Immaculate Conception Catholic Church in Chicago. Her family, she said, has still recovered from the shock of Daniel’s death.

“I feel so lost,” she said. “Gun violence needs to stop. I don’t want another family going through what my family is going through.”

“Gun violence needs to stop. I don’t want another family going through what my family is going through.”

Ms. Dominguez was speaking at the culmination of a peace walk through one of Chicago’s more troubled neighborhoods, Brighton Park. It was part of a Via Crucis, or Way of the Cross, procession meant to “acknowledge the burden of violence in the Hispanic community,” according to the Archdiocese of Chicago.

One of the event organizers, the Rev. Manuel Dorantes, told America that a group of young people led the effort to have his parish tackle the issue of gun violence. More than 50 of them attended the March for Our Lives in Washington earlier this month.

“We need to not necessarily be the ones to lead and say, ‘This is the way I want it,’ but ask, ‘What do young people want?’” Father Dorantes said, adding that gun violence is an issue “the church cares deeply about. It’s part of our consistent ethic of life teaching.”

Cardinal Blase Cupich, the archbishop of Chicago, joined in the procession and addressed the crowd during the rally afterward.

Delivering remarks in English and Spanish, the archbishop praised the “courage” of young people who took to the streets to demand an end to gun violence.

“These young people who come from places some might call the margins have claimed a place at the center of our nation and have given all of us a lesson in courage,” the cardinal said.

“They came from the war zones of our city and spoke the truth—that their lives are sacred—and held those in power accountable for the bloodshed they know all too well,” he continued. The teenagers standing beside him shouted, “No more silence, end gun violence!” during the address.

Cardinal Cupich: “These young people who come from places some might call the margins have claimed a place at the center of our nation and have given all of us a lesson in courage,”

One of those young people was 16-year-old Diego Garcia, a parishioner at Immaculate Conception who traveled to Washington for the march.

Wearing a white “March for Our Lives” T-shirt on Friday, Mr. Garcia told America that he hopes other young people “will realize that their voices are important and not stay quiet.”

“So many people are dying so fast in our community,” he said. “The value of life is greater than the value of a weapon.”

Ashley Calderon, a 22-year-old woman from the neighborhood, attended the rally. She sustained a gunshot wound to her foot about six weeks ago while at a party and said the violence has to stop.

“We need to stop this. People just have random guns, they don’t even know how to use them, just start shooting, and people get hurt,” she told America.

The event started with a re-enactment of the Last Supper at another Catholic church before the procession, which weaved its way past a handful of Brighton Park churches. Several hundred marchers joined in along the way, following behind a re-enactment of Jesus being scourged by Roman authorities. Along the processional route, people stood on porches and snapped photos with their phones and blessing themselves. Some hung out of top-floor windows for a better glimpse. A truck carrying musicians and singers led the procession, with hymns in English and Spanish providing a soundtrack as members of the Chicago Police Department bookended the marchers.

At the end of the route, a crowd of several hundred gathered in front of Immaculate Conception to watch a re-enactment of Jesus’ crucifixion. An actor portraying Jesus, wearing a crown of thorns and covered in artificial blood, carried a large wooden cross through the crowd. He paused for a moment under a nylon banner, with the March for Our Lives logo, affixed to the side of the red-brick church before taking his place on the cross.

The banner read: “Dejen los ‘Pensamientos y Oranciones’ a nosostros. Legisladores, legisen! Prohiban las armas de asalto AHORA! Pedimos acción!” (“Leave the ‘thoughts and prayers’ to us. Legislators, legislate! Ban assault weapons NOW! We ask for action!”)

Michael J. O’Loughlin is national correspondent at America and author of Hidden Mercy: AIDS, Catholics, and the Untold Stories of Compassion in the Face of Fear.