"Brandon was a good guy. He had a family," Wilson said.
It was August 30 of last year, the height of Hurricane Harvey. Investigators say Thomas was outside of his apartment in Houston's south side.
His fiancee said he was on the phone when a teen who lives at the complex was also in the parking lot.
Around the same time, a silver car drove into the complex and witnesses told investigators four or five people got out and started shooting.
The teen was shot and he survived. Thomas did not.
Investigators say multiple weapons were used, but so far only one suspect has been arrested and they believe there are more out there. That suspect is Desmond Williams.
He was out on bond at the time of the shooting for allegedly shooting someone else six months earlier. Williams is now behind bars and charged with capital murder.
The Harris County Sheriff's Office is still searching for the other suspects who were with Williams. They're hoping someone who knows something comes forward.
"I just want somebody to come forward so justice can be served for my son," said Wilson.