I'm Lester Holt tonight on Dateline, a mother who will stop at nothing to find her son's killer.

I remember telling him,

I'm so sorry, Mommy wasn't there for you.

I cannot rest until I find out who did this and why, who shot him.

Was he shot while he was in the park?

In the car.

Who lives there?

Well, like, why would he be there?

The only trouble that he would ever get in would be with women.

He was texting, making phone calls all at the same time.

You finally see that video from the police camera.

I can't get that image out my head.

Our son is on the ground dying.

My family immediately went into action.

She found out a lot of things on her own that police didn't tell her.

Yes, she needed to keep investigating.

I knew that I had to do the work myself.

You only have a 26% murder file right now.

You know, it's the community that's failing here.

My son deserves justice.

I will keep fighting for him until my last breath.

Here is Josh Mankowicz with the story of somebody.

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