The prosecution is expected to wrap its second-degree murder case against George Zimmerman today with the mother of Trayvon Martin testifying that the person heard screaming for help on a 911 tape is her son.
Sybrina Fulton, the mother of the slain teenager, will take the stand on the ninth day of testimony in the Florida trial.
Fulton and Tracy Martin, Trayvon Martin's father, have been present every day of the trial and endured testimony about the shooting and their son's wound that at times have prompted them to abruptly leave the courtroom.
Zimmerman, 29, maintains he shot the unarmed teenager in self-defense after he was confronted and attacked by Martin, 17, on Feb. 26, 2012. Prosecutors allege the former neighborhood watch captain profiled, followed and then shot Martin as he was walking back to the residence where he was staying as a guest.
Fulton's testimony could be particularly powerful for the jury of six women.
Catch up on all the details from the George Zimmerman murder trial.
A major point of contention in the trial is who is heard screaming for help in the background of 911 tapes the night Martin was killed. Fulton claims it is Trayvon Martin screaming, while Zimmerman's father insists that it is his son's voice that is heard.
The prosecution hopes that Fulton's testimony will have an emotional and convincing impact on the jury and that the jurors will tie her words to the opinion of FBI audio expert Hirotaka Nakasone who testified earlier in the trial that it was not technically possible to identify the voice.
He said, however, the best person to identify the voice would be someone who is intimately familiar with the voice.
Fulton has shown that she can be a powerful voice for her son. During jury selection she said, "When I see someone wear a hoodie, when I see a teenager, when I see a kid listening to their earphones, kids walking home from school, everything reminds me of Trayvon."
It is unclear if Martin's father will also take the stand because he initially told police he doubted it was the voice of his son.
Zimmerman's father, Robert, may eventually testify for the defense. He has been consistent that the screams for help are from George Zimmerman.
Trayvon Martin was scheduled to graduate high school last month. Since his death, his mother has gone from a life she described as average to a grieving mother who has advocated for her son and victims of gun violence in the U.S. and abroad.
The prosecution is nearing the end of its case without a witness who saw the shooting or who started the fight. The dominant voice in the courtroom so far has been that of Zimmerman through the frequently played police interrogations of him describing what happened that night.