For as much pain as Bivines felt for the slain police officer and his family, as much as she hoped the killer would be caught, her heart broke all over again for her own son, Ivan Simmons. It's been almost a year since the 17-year-old was gunned down in Nicetown, and his killer hasn't been found yet.
She tries to check in with detectives once a month, because she's lost faith that they might give her a courtesy call. It might be a lack of manpower, or too many murders to keep track of, or uncooperative witnesses, or detectives desensitized to her pain.
Every time, she's told the same thing: "No leads. No witnesses. No one's talking."
Yet police tell her to be patient. They reassure her that there's no statute of limitations on murder.
Not much a comfort. There's also no statute of limitations on her grief.
"It's almost like you're the victim twice," she says.
We all know there are too many victims. To date, 259 officers in the city have been killed in the line of duty, that since 1828. Just this year alone in Philly, 348 people have been murdered - 43 percent of those cases still unsolved.
It's no secret that most homicide victims are African American males, in many cases, poor and struggling.
In other words, invisible.
Nobody's naive enough to think the police have the manpower to deploy a full army of helicopters and dragnets for every homicide. You'd need to double the police force just to do half the work investigators put in to find Cassidy's killer.
Still, you can't help but wish that every victim would get the same urgent response - black or white, rich or poor, in or out of uniform.
It's been eight months, and the person who shot and killed Gregory "Mustafa" Lucas, 37, an Army vet fighting the demons of addiction, still hasn't been captured. Detectives have told his family that leads have dried up, says his sister, Shanda Lucas. A "cold case," is how they've described it.