Nothing can prepare you for losing your child in a gruesome murder. And for one Florida woman, what's happened since that day has made things even more intense, even pitting family member versus family member in court.

A public appeal to find a man caught on surveillance video, just minutes before 20-year-old Shelby Farah is gunned down inside a cellphone store in Jacksonville, Florida.

Shelby was a beloved college student, community volunteer, and mentor to the young girls she coached on her former high school's cheerleading squad.

An outpouring of support from friends and neighbors is a testament to how much Shelby meant to the community.

Surveillance video from inside the store captures the last few moments of Shelby's life, seconds before she's robbed at gunpoint.

Shelby, the store manager, works alone while cops say the suspect paces outside, casing the place, waiting for customers to leave before making his grisly move.

In a strange twist, Shelby's mother Darlene tells our Jacksonville affiliate, WJXT, that when she drove her daughter to work that morning, she actually quizzed Shelby on what to do if this terrifying scenario ever happened.

"I asked her, I said, 'Shelby what would you do if you ever got robbed? Would you cooperate?'" said Darlene. "She said 'Mama, I'd give 'em the keys to my car. I'd load the stuff up for 'em.' She said, 'I can't believe you asked me that.'"

Sadly, police say Shelby did everything she was supposed to do, and it didn't matter. The gunman took point-blank aim and shot Shelby without flinching, execution-style.

"Pointed the gun at her, demanded the money. She cooperated, she was doing what he asked, and when she handed him the last bit of money he fired three rounds, killing her," said Jacksonville Sheriff's Lt. Rob Schoonover.

Leaving her friends, her siblings and her grieving mother in agony.

Mom and 16-year-old son Caleb, Shelby's brother, didn't have to wait long for police to catch the suspect. Hours after their interview police got a tip and arrested the man in the surveillance video: 21-year-old James Rhodes, a known felon with a history of assault and weapons charges. According to police, James Rhodes's own family turned him in, scared to death after he threatened to kill them if they went to the cops.

Rhodes eventually confesses and is charged with first-degree murder, armed robbery, and aggravated assault.

And as Shelby is laid to rest, her killer behind bars, the Farah family thinks they can finally find peace.

But in a shocking turn of events, Rhodes's confession turns out to be just the beginning of a long and torturous odyssey that ultimately leads to a bitter feud between defense attorneys and the prosecutor, and mother against son.

While her family waits for her alleged killer to be brought to justice -- a bitter battle is going on inside and outside the courtroom.

Darlene Farah watched the video of her daughter shelby being murdered, now describes what it's like every time she faces the man who killed her in court.

"It's hard to sit there and look at somebody that took your child's life away and to just stand there like he don't even care, like it's nothing to him," said Darlene.

Darlene has shown up for every single court appearance since James Rhodes confessed to shooting her daughter. But two and a half years after Rhodes's confession Darlene is still waiting for justice, all because of an ongoing feud between prosecutors and the defense that's bogging down an seemingly endless series of pre-trial motions.

The court case has set off a family fued. Affiliate WJXT has been following the story of what has become an agonizing journey that ultimately pits mother against son.

Shelby's brother Caleb wants his sister's killer sentenced to death. His mother wants him to get life.

Rhodes's defense team says this would all be over if the Florida state's attorney would allow Rhodes to cop a plea to first-degree murder and serve a life sentence. But prosecutors want the death penalty and they're not backing down.

Rhodes's attorneys filed a motion to have him declared "intellectually disabled." With an IQ of 72 he's just two points above the legal limit for capital punishment. That follows a U.S. Supreme Court ruling that mitigating factors should be considered when anyone with a borderline IQ between 70 and 75 faces the death penalty.

There's been no ruling on that and 19 other motions filed by the defense, all of which now has a beleaguered Darlene asking that the death penalty be taken off the table.

"It's not going to bring my daughter back," said Darlene. "Who are we to put a date on anybody's life? Only God can."

Believe it or not, Darlene is so frustrated with the prosecution's pursuit of the death penalty that she actually testified for the defense, the legal team representing her daughter's killer. It was her attempt to get this case settled so Shelby can rest in peace.

Prosecutors also showed Darlene's 19-year-old son Caleb the video of the very moment Shelby was viciously murdered. It haunts him, and that's why he wants his sister's killer to pay with his life.

Jury selection is now set for May 2016, three years after Shelby was killed. A family now divided by grief and anger is still holding on to the hope they can one day soon lay this tragedy, and Shelby, to rest.