(UVALDE, Texas) — For 19-year-old Sam Schwartz, arriving in Uvalde, Texas, “was unlike anything I’ve ever seen.”

“Getting off that bus and walking to that memorial, there were 21 crosses around the fountain,” he told ABC News, calling it the “most deeply disturbing thing I’ve ever seen.”

Schwartz’s visit this week was part of a summer campaign organized by Patricia Oliver and her husband.

The Olivers’ cheerful and athletic son, 17-year-old Joaquin, was among the 17 people killed in the Parkland, Florida, high school mass shooting in 2018. Patricia Oliver and her husband have become outspoken advocates for gun control, and each summer, they ramp up their efforts to mark their son’s Aug. 4 birthday.

This summer, in honor of what would’ve been Joaquin’s 23rd birthday, they’re taking their mission on the road, visiting 23 cities across the country that have been impacted by gun violence, from Columbine, Colorado, to Sandy Hook, Connecticut. The campaign is called “Guacathon,” named after Joaquin’s nickname, “Guac.”

The tour aims to unite families of gun violence victims and offer a way for Americans “to get a closer look at what gun violence does to families, to communities,” Oliver told ABC News.

Through this unity, families impacted by gun violence could have a better chance at making the legislative reforms they’re looking for, added Schwartz.

This campaign is just as personal for Schwartz, whose cousin and best friend, 14-year-old Alex Schachter, was killed at Parkland.

“I would feel in a very depressed state if I chose not to do anything,” he said. “A lot of other people on this bus right now feel the same about the loved ones they lost.”

On Tuesday, the “Guacathon” bus stopped in Uvalde, where 19 children and two teachers were shot and killed at Robb Elementary School in May 2022, in one of the latest school massacres to shake the nation.

“I’ve known these families for a year now,” Schwartz said. “Going to their community and seeing what they go through … that’s how you get to know someone — especially in this fight.”

Schwartz said he’s befriended Jazmin Cazares, a Uvalde teenager who also turned to activism after her 9-year-old sister, Jackie, was killed at Robb Elementary.

“It’s always nice to talk to kids my age, I feel like I can share my experiences,” Schwartz said.

After visiting the memorial, the “Guacathon” participants held an emotional rally where Uvalde families shared stories of their loved ones and urged people to vote for gun reform.

“Seeing all the families coming together, expressing their feelings … at the end of the gathering, they were relieved,” Oliver said. “That was our purpose — let Joaquin bring some relief, some kind of comfort.”

To Oliver, the most poignant moment was when she saw one grieving Uvalde mom, who seemed burned out in recent months, come to the rally and speak.

“She reminded me of me,” Oliver said. “Even though you see me on the road for so long, I struggle. When I come back to the hotel or I go back home, maybe I have to spend two days in bed.”

“She felt that need to express herself again. And I was so glad to hear from her,” she said.

“I feel Joaquin made that happen,” she added.

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