Kenneth Singleton, 38, was shot and killed during a pool tournament on Monday night in an East Mount Airy bar.
It happened at the Uptown Cafe along the 8100 block of Stenton Avenue.
Officers responded just before 11 p.m., where they found Singleton with multiple gunshot wounds.
Investigators say Singleton got into an argument with another man, which escalated into gunfire.
Police said the shooter fled after shooting Singleton repeatedly in the torso and arm.
Lisa Dixon said her son was simply in the wrong place at the wrong time.
"He didn't even drink. So, I couldn't understand, you know what I mean? But he did like to play pool," Dixon said.
The victim's uncle, Shedrick Felton, said he had been with his nephew at the café shortly before the shooting.
"And then I got a call maybe 20 minutes later, and they like, 'You know they killed Scooter?' I said, 'They killed my nephew, what? I was just here,'" Felton said.
The killing has reopened deep wounds for Dixon, who lost another son to violence four years ago.
Surveillance video from that case shows an ambush-style attack that killed 30-year-old Brandon Dixon on the 1000 block of East Mount Airy Avenue, just a few blocks away.
Mom mourns son killed in brazen daytime shooting in Philadelphia
Dixon said her faith is helping her cope with the loss of both sons.
"It's God's plan, and that's all I got to lean on. It's God. It's just God, and I can't change God's plan. I just have to learn how to deal with it," she said.
As she grieves, Dixon said she is holding on to memories of the small moments she shared with her beloved son.
"His smile. The way he cares for his mom, and his family. I'm going to miss him," she said.
Singleton leaves behind a 5-year-old daughter.
A $20,000 reward is being offered for information leading to an arrest and conviction in the case. Anyone with information is asked to contact the Philadelphia Police homicide division.