PHILADELPHIA — The mother of Trayvon Martin, the unarmed Florida teenager whose fatal shooting by a neighborhood-watch volunteer has provoked a national debate over racial profiling and gun laws, appealed to a crowd of black advocates in Philadelphia on Friday to “use my broken heart” to prevent a repeat of what happened to her son.

“My message to you is, please use my story, please use my tragedy, please use my broken heart to say to yourself, ‘We cannot let this happen to anybody else’s child,’ ” Sybrina Fulton said during a talk to a National Urban League meeting. She received a standing ovation.

Her appearance came on the heels of comments by a juror in the case, who said Thursday that she believed George Zimmerman “got away with murder.” Although the juror’s comment, in an interview with ABC’s “Good Morning America,” has been the subject of much conversation at the conference, Fulton did not address it in her remarks Friday. (Fulton late Thursday issued a statement saying it had been “devastating for my family” to hear what “we already knew in our hearts to be true.”)

On Friday, she spoke about the faith that she said has carried her through since February 2012, when Zimmerman killed her son, 17, as he was walking home after buying snacks at a convenience store.

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“I speak to you as Trayvon’s mother,” she said. “I speak to you as a parent, and the absolutely worst telephone call you can receive as a parent is to know that your son — your son — you will never kiss again. I’m just asking you to wrap your mind around that, wrap your mind around no prom for Trayvon. No high-school graduation for Trayvon. No college for Trayvon. No grandkids coming from Trayvon, all because of a law, a law that has prevented the person who shot and killed my son to be held accountable and to pay for his awful crime.”

A jury acquitted Zimmerman July 13 of all criminal counts in the slaying.

Fulton and Trayvon’s father, Tracy Martin, are pressing the federal government to consider federal civil-rights charges against Zimmerman, and they are waging a campaign to amend expanded self-defense statutes like the one in Florida, known as “stand your ground” laws, that extend beyond the home the right to use force in a dangerous situation and in some states, offer immunity from civil liability.

About 6,000 people are in Philadelphia for the Urban League meeting, which comes against the backdrop of plans to commemorate next month the 50th anniversary of the 1963 March on Washington for Jobs and Freedom, in which the Rev. Martin Luther King Jr. delivered his now-famous “I Have a Dream” speech.