Hundreds gathered for a candlelight vigil on Friday night at Mernda Skate Park in Melbourne's north, in the suburb where Aidan Becker was killed a week ago.
There were tears and heartfelt tributes from mourners for the security guard and his family.
"We stand here as family broken. I don't know how we heal," his tearful mother told the large crowd.
"My beautiful boy would have done it all again in a heartbeat. Because that's the boy he was."
Police allege Mr Becker was allegedly pursued by a group of teenagers and attacked after coming to the aid of a 14-year-old boy at the train station about 6pm on March 6.
Despite the efforts of paramedics, the 22-year-old died at the scene.
Four male teens were arrested at the scene and charged with murder and armed robbery.
The schoolboy's family paid tribute to Mr Becker in a statement released by Victoria Police on Tuesday, saying they were "deeply saddened by this heartbreaking loss".
"He showed extraordinary courage and compassion in risking his life to save our son," they said.
Dozens of bouquets and several handwritten notes were left near the site of the alleged crime, with local residents hailing Mr Becker a hero.
The vigil on Friday night brought the community together after the alleged murder sent shock waves through it.
"We've come together to reflect on the life of a remarkable young man," Farell Paton, a community member said.
"In a moment when someone vulnerable needed help, Aidan stepped forward. That instinct to protect, to stand up for someone else, speaks volumes about who he was."
His mother took time to thank one of the first responders who attempted to save her son's life before paramedics attended.
"You are my hero," she said.
"Thank you for telling my boy his family loved him because those would have been the last words he heard."
Assumption College, where the 22-year-old attended high school, described him as a "young person who was mature, humorous and kind-hearted".
"We extend our heartfelt sympathy to Aidan's family and friends at this difficult time," the school said on Friday afternoon.
Victorian Premier Jacinta Allan broke down in tears after visiting the station earlier this week.
"It's an opportunity for me to sit and listen," she told reporters.
Ms Allan said her government's Violence Reduction Unit was on the ground working to understand what led to the incident.
The eldest of the four accused teens, Mike Pikos, 18, appeared before Melbourne Magistrates Court on Sunday and was remanded in custody to return to court on June 24.
A 16-year-old from Whittlesea, a 17-year-old from Geelong and a 17-year-old from the City of Yarra were charged with murder and armed robbery.
They will appear at a children's court at a later date.
