SANFORD, Fla. -

Five out of the six jurors in the George Zimmerman trial are moms. This weekend they will likely be haunted with a question raised after Friday's witness testimony:  Whose mom should they believe?

On the rainy night 29-year-old Zimmerman killed 17-year-old Trayvon Martin at The Retreat at Twin Lakesgated community in Sanford, Fla., Jenna Lauer called 911. The recording of her call captured desperate screams for help, a gunshot and then silence. 

In court on Friday, the victim's mom Sybrina Fulton and the defendant's mom Glady Zimmerman both claimed the person who was screaming for help on the Feb. 26, 2012 fatal shooting was their son.

"I heard my son screaming," Fulton said. And how did Glady Zimmerman know that the screamer was her son? "Because he is my son," she said.

Before the trial began June 9th, forensic audio experts were also on dispute over who the screamer in the 911 call was. While a prosecution's expert claimed it was Trayvon, the defense experts said the identity of the screamer could not be determined with certainty.

Tom Owen, forensic consultant for Owen Forensic Services and chair emeritus for the American Board of Recorded Evidence, said in 2012 that he used voice identification software to rule out Zimmerman, the Orlando Sentinel reported.

The ambivalence of the forensic experts' findings never made it to the jurors ears. Judge Debra Nelson banned some of the audio expert's testimony on June 22nd. 

On July 1st, prosecutors called to the witness stand Hirotaka Nakasone, an expert on voice recognition systems of the FBI's operational technology division. He was one of the experts who said the screamer could not be identified. His testimony set fertile ground for attorneys to call both mothers up to the witness stand.

"The familiar voice recognition happens pretty much every day," Nakasone said, while adding that a person familiar with the voice could contribute to an identification effort.

On Friday, the prosecution also called to the witness stand Trayvon's brother Jahvaris Fulton. He said he was sure it was his brother, and that he had listened to the recording 10 to 15 times.

The defense was quick to point out that Trayvon's brother had not always been so sure. At one point, defense attorney Mark O'Mara said Jahvaris' testimony was impeached by earlier statements he made during a TV interview. Nelson disagreed.

"I was clouded by shock and denial and sadness," Jahvaris Fulton said. "I didn't want to believe that it was him."

The defense called to the witness stand Zimmerman's uncle Jorge Meza. His testimony may have been more convincing, since he claims he never for a moment doubted it was his nephew screaming. 

"It was George Zimmerman screaming for his life," said Meza."I felt it inside of my heart."

For nine days, the jury  listened to witnesses brought forward by the prosecution. They were presenting evidence to support a second-degree murder charge. Now the defense will be presenting witnesses to prove that Zimmerman killed in self-defense.

On Friday, both the prosecution and the defense implied that hopeful thinking was clouding both the defendant's and the victim's relatives' testimony.

When O'Mara confronted her with doubt, Fulton was assertive.

"What I hope for is that this would not have happened and he still would be here," Fulton said.

It is not easy to say how relevant the mothers' testimony was to the jury. Some experts assume that the mothers in the jury will empathetic, but  the five mothers did not shed a tear in the courtroom.

It is likely that jurors will never know the critical answer to the question: Who was screaming for help the night of the Feb. 26, 2012 fatal shooting?

Jurors must rely on other evidence. During the trial, the defense will continue to show pictures of Zimmerman's injuries and the prosecution will continue to highlight that Zimmerman got off his car and that his gunshot silenced the screamer.