Manuel Oliver is using his brushstrokes to speak on behalf of his son and the 16 other victims of the Parkland, Fla., high school shooting.

In a March 10 video, now seen by more than 2.3 million people, a portrait of his son Joaquin “Guac” appears in the middle of a white mural as Oliver paints the words: “We demand a change.”

He signs the mural, “Guac’s dad, love you forever.” The artwork was part of a Miami exhibit to honor the Parkland victims.

“It became something viral, we weren’t expecting that,” Oliver said in an interview with The Washington Post. “It became a movement by itself.”

One month later, Oliver and his wife Patricia traveled to Los Angeles to paint another mural of his son. This time, he created Joaquin’s silhouette surrounded by a target.

The words “We demand 2 stop this BS” are painted above his head. Oliver hammers holes in the canvas that he then covers with sunflowers.

Oliver, who is a Miami-based artist, plans to travel around the country to paint 17 murals total in honor of each person that was killed. He has created three murals so far.

The art murals are part of a larger movement begun by “Change the Ref,” a nonprofit organization founded by the Oliver family in hopes of empowering and educating young people while changing the conversation on gun control.

“This young generation is showing that they are demanding for new leaders,” Oliver said. “The fight we are having next to these kids is against any group that tries to put money in any politician’s pocket. We need to clean how we are represented right now, and the only way to do that is to empower future leaders.”

The name of the organization was inspired by a conversation Oliver had with his son only days before he was killed. Joaquin and Manuel were frustrated by a basketball referee’s calls during a game they were playing.

Joaquin noted that the referee may have had connections with the other team.

“Immediately [after the shooting] I remembered that conversation I had with my son, about the need to have a fair game and the need to change the ref,” Oliver said. “If we have politicians that have agreements with powerful groups or lobbyists, they don’t have even an intention of starting a debate.”

“Change the Ref” plans to register young people on-site as the murals are painted, and launch a voter registration app alongside youth forums. They’ve set up a GoFundMe page to raise money for their efforts.