(CNN) Jill and Phil Henderson have to do it all over again.

Again, they've flown from their home in Austin, Texas, to Greece. Again, they will sit through a trial trying to understand attorneys' arguments by reading their facial expressions.

And again, they will hope it all ends with justice for their son.

"No one should get away with murder," Jill Henderson says. "No matter who the victim is and no matter who the defendant is."

Her son, Bakari Henderson, a 22-year-old recent college graduate, was beaten to death by a group of men on the Greek island of Zakynthos in the summer of 2017. Despite video evidence of the encounter, no one was convicted of murder during a 2018 trial. The case is being retried on appeal beginning Wednesday.

His parents will be there, reliving the worst moments of their lives and hoping for a different outcome for the child Jill Henderson called her "shining light."

'Justice should be served'

Greece was just one of a handful of stops Bakari had planned to make that summer in Europe. He wanted to take photos for a clothing brand he was soon launching. His mother says he always had an entrepreneur's mind.

It was in his DNA, she says.

"Even as a kid ... in kindergarten, he was on the playground and he sold his classmates little crystal rocks -- he called them crystals," his mother says. "We got a call from the school and we had to explain (to him) that you can't really sell rocks because they're not yours."

Bakari went on to graduate from the University of Arizona with a degree in Business and Entrepreneurship.

The summer after graduation, in July 2017, he joined three friends, including Daniel Brown, in Zakynthos. Brown, who grew close to Bakari after they met during freshman year, was familiar with the island and had visited family there almost every other summer of his life.

Bakari Henderson in his childhood

"It was amazing," Brown recalled of the trip. "An incredible time filled with dinners on cliffsides, looking at the most beautiful sunsets you could ever imagine."

It all came to an abrupt end.

Footage from two surveillance cameras captured parts of what happened on July 7 that year. The first seems to show Bakari taking a picture with another man and a woman. A third man confronts him and the two seem to engage in a fight.

In the second video, Bakari is seen running, followed by a pack of men who throw him on the street and begin punching and kicking him. He lays on the floor motionless as passersby begin breaking up the fight. Eventually, an ambulance takes him away and he's pronounced dead.

Jill Henderson says this June 2017 picture is the last family photograph they took altogether. Pictured are Bakari, his sister Jory, Jill, Phil and Bakari's brother, PJ.

Attorneys told his family the videos would make the case a no-brainer. They promised justice.

"Evidence shows this was a cold-blooded murder as a mob attacked Bakari, attacking him with punches to the head and torso," Andreas Patsis, the attorney who represented the family during the first trial, had said in a statement.

Nine men were arrested -- the majority of them Serbian nationals -- and faced intentional homicide charges, which carry sentences of up to life in prison.

But the Greek court convicted six on a lesser charge of deadly assault with sentences ranging from five to 15 years. The three others were convicted of simple assault and were released, according to Greek media.

"I felt like we had, in my mind, been betrayed," Jill says. "Bakari was a human, he wasn't just some random object that got tossed away. He actually meant a lot to his family and friends and we just think justice should be served."

Hopeful but wary

Attorneys in the US were baffled by the first decision.

"We were confident that the system there... would provide justice for Bakari and the Henderson family," Earl Ward, a New York attorney who's been helping the family navigate the case, told CNN. "But in the end that really didn't happen."

Greece does not have a double jeopardy law that would prevent the men from being tried on the same homicide charges.

Bakari and Phil Henderson

Attorneys the family has been working with are hopeful for a homicide conviction this time around, Jill Henderson told CNN. But they were hopeful last time too, she says.

Bakari's parents will be there, regardless. They haven't booked a ticket back home yet. They're prepared to stay for as long as necessary to see justice for their son's killing.

"That looks like all nine defendants getting the maximum sentence," Phil Henderson says.

How they remember him

Brown will be one of the witnesses for the trial. He still has a tough time going back to that night. Instead, he remembers all that he loved about his friend.

The two of them snapped a picture together the day before Bakari died. They were on the edge of a cliff, a secret spot Brown was familiar with that was only popular with locals.

Brown took his friend's phone and recorded him jumping into the water. And then, as he tried handing it back, Bakari's phone fell and shattered.

"I was extremely distraught," Brown says. "I knew he had to spend the rest of his time in Europe taking pictures on that phone because he didn't bring a camera."

Bakari Henderson and Daniel Brown in Zakynthos island, in July 2017

Bakari was unbothered.

"He just put his hand on my shoulder and he goes, 'Dude, chill out, it's just a material object,'" Brown said. "These days, it's all I can think about."

Phil Henderson says he'll remember his middle child as "the most outgoing, the loudest, the one who'd always want to make you laugh."

"He's fun, loving, very generous and he loved people," he says. "Everywhere he went he would make friends."

In his honor, his parents created the Bakari Foundation, to connect with other families who have lost loved ones to violence.

This year, Jill says, they're planning a retreat to Costa Rica. Soon, they want to offer counseling and legal counsel services.

"Because of his love for travel and learning about new cultures and meeting people we decided to have one of the focuses be on providing a transformative healing experience," she says.