TAMPA, Fla. – Maria Rodriguez teared up as she thought about another family having to feel the sorrow and pain hers has felt since Oct. 19.

Rodriguez’s stepson, 20-year-old Anthony Naiboa was the third victim in a string of unsolved murders in Seminole Heights. She and Naiboa’s father, Casimir, have remained heavily involved in the community since his death.

TIMELINE: 4 murders in Tampa neighborhood, killer at large

PHOTOS: Victims in Seminole Heights killings

On Tuesday, just hours after a fourth victim was shot and killed at random in Seminole Heights, Rodriguez and Naiboa were out walking the streets, talking to people, desperately looking for answers.

Sitting still is not an option.

“We’re trying to have justice for our son,” she told 10News.We’re speaking out because we need justice. This needs to stop.”

Walking alongside them: retired Army veteran Johnnie Compton. He’s not an actual detective but he volunteered to help the family in any way he could.

“Because I care,” he said.

Compton says two decades ago he received a liver transplant from a man who’d been murdered. Since then he says he’s worked to help solve homicides and track killers and has even been recognized by the Tampa police department.

He met the Naiboa’s at the spot where Anthony was killed the night of his vigil and the connection was immediate.

“To be standing with another family with a special needs kid like I have and knowing how devastated you have to be to lose your child in such a needless fashion, what if that was my daughter,” Compton said.

Unlike the first three murders, a witness was able to provide a suspect description following Tuesday morning’s shooting. The Naiboa’s hope that’s the break police need to finally catch the killer.

“It’s just frustrating because they haven’t even caught this criminal and deep down inside I feel it’s the same person killed my boy,” Rodriguez said crying.

“They need to get him off the street, they really do.”

Until evidence says otherwise, Tampa police are relating the Tuesday, Nov. 14 shooting death in the Seminole Heights neighborhood to the three earlier October murders.

RELATED: Latest Seminole Heights victim was on his way to feed homeless

Tampa Police Chief Brian Dugan identified the victim as 60-year-old Ronald Felton. It's believed Felton was crossing the street to meet with someone when a suspect came up from behind and shot him, Dugan said.

There remains a $41,000 reward for anyone with information leading to the arrest and conviction of the October killings. People can call Crime Stoppers at 1-800-873-TIPS.

►Make it easy to keep up-to-date with more stories like this. Download the 10 News app now.

Have a news tip? Email desk@wtsp.com, or visit our Facebook page or Twitter feed