Father's Grief At Baby Son's Death During Bourke Street Rampage

The father of a baby boy killed in Melbourne's Bourke Street rampage has described listening to his final heartbeats and "trying desperately to hold onto the moment".

Three-month-old Zachary Bryant was in a pram with his big sister Zara when

James Gargasoulas, now 29, drove his car along footpaths and through a busy pedestrian mall while in a drug-induced psychosis on January 20, 2017.

He killed six people and injured dozens more.

Zachary and Zara were thrown from the pram, which became wedged in the smashed windscreen of a stolen car driven by Gargasoulas.

Zara survived despite suffering serious head injures, but Zachary died in hospital.

On his way to be by their side, dad Matthew had no idea of their condition.

"At that point all I could do was pray, pray for some kind of miracle that they would pull through, but in my heart I already knew my son had already left us,"

Image: AAP

Bryant told a plea hearing for Gargasoulas in the Supreme Court of Victoria on Wednesday.

"I held him for the last time, trying desperately to hold onto the moment, not wanting to let go."

After his life support was turned off, the next time Bryant and wife Nawwar Hassan-Bryant saw their baby son, he was "freezing cold" before his burial.

"When Zachary left us, I felt a part of me die with him," Bryant said.

"I feel a constant guilt and failure that I was not there to protect my son and daughter."

Nawwar Hassan (centre) and Matthew Bryant (right), the parents of Zachary and Zara Bryant. Image: AAP

Hassan-Bryant described Zachary as a "gentle and calm soul who was always so easy to please", and who they'd welcomed to the world only months earlier.

Their statements were two of about 50 that were read or tendered in court this week before Gargasoulas is sentenced.

Melinda Tan, the wife of victim Matthew Si, 33, told the court Gargasoulas was a coward.

"I wear the label of a widow and you of a murderer," she said to the killer.

"May you suffer the consequences of your actions and live in eternal fear."

READ MORE: Bourke Street Scene Was 'Madness', Court Hears

READ MORE: 'You Will Never Be Forgiven': Bourke Street Killer Faces Families Of Victims In Court

Melinda Cleland was in the city to meet a friend for lunch when she was bounced off a concrete wall during the attack.

She said she had a "split second" to decide what to do to save her life.

"I often wish I had no memory of the event," she said, adding she remembers "every sickening moment" and suffers flashbacks.

"(I remember) the sound of my bones crunching inside me as I bounced off a concrete wall," she said.

"I have physical injuries that remind me daily that life has changed."

Melinda Cleland. Image: AAP

Gargasoulas previously pleaded not guilty to killing Zachary, Mr Si, Yosuke Kanno, 25, Bhavita Patel, 33, Jess Mudie, 22, and Tahlia Hakin, 10, but was found guilty by a jury.

Gargasoulas' barrister Theo Alexander previously submitted that his client's moral culpability should be reduced because of his mental illness and that he should one day have the opportunity for parole.

The plea hearing continues on Thursday.

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