With his son on his lap and safety controls overridden, Christopher Browne drove an ATV up his driveway and did a burnout in a paddock trying to scare his sister.
But the buggy rolled and his two-year-old son Lincoln was thrown and fatally crushed under its weight.
Browne admitted he was to blame for his son's death on Christmas Day 2020 and pleaded guilty after a Victorian County Court judge indicated he would avoid prison time.
But three judges in the state's Court of Appeal on Friday ruled that was wrong.
They sentenced him to 15 months behind bars after finding striking similarities between his case and that of another Victorian father jailed for three years after his nine-year-old daughter was killed.
Browne, who must serve at least six months, was given a moment to hug and say goodbye to his pregnant wife before being taken into custody.
The couple learned they were expecting their fifth child after prosecutors filed the appeal. They have one living child and had stillborn twin girls before Lincoln's birth.
The appeal judges found Browne's offending was serious and his moral culpability was high.
He had deliberately driven dangerously by doing the burnouts or doughnuts and had also deliberately flouted built-in safety features on the buggy by sitting on top of a clipped-in seatbelt, overriding a safety lock that would have limited the speed to 25km/h.
Lincoln had been sitting on Browne's lap, and Browne's sister was in the passenger seat of the buggy, which should only have had two people on board.
"(Browne) drove in a manner deliberately calculated to cause the buggy to lose traction and deliberately set out to drive in a manner designed to scare his sister, who was a passenger in the buggy," the appeal judges said.
But they also took into account mitigating features including that he was a man of good character with an impressive work history and who makes valuable contributions to his local community.
He has family support and will experience anxiety in prison given his wife's pregnancy - all factors warranting a merciful sentence, they said.
Browne had already completed more than 100 hours of the 250 hours of community work that Judge Michael Cahill had originally imposed.
He had also been ordered to undergo treatment for post-traumatic stress disorder.
His PTSD had factored into Judge Cahill's sentence, but in the appeal Victoria's Chief Crown Prosecutor Brendan Kissane questioned the extent to which this should have mitigated the sentence.
"It's trite to say any parent who is involved in the death of their child would be grief-stricken, would be suffering, or would suffer from stress and anxiety, and the distinction, if there is one, is not such to warrant the distinction in sentence," he said.
Browne's barrister, Jason Gullaci SC, said Browne had admitted to police about trying to scare his sister, doing doughnuts and flouting seatbelt rules.
"He has taken full and direct responsibility for the devastating consequences of his very reckless behaviour," he said.
He'll be eligible for parole in August.
Australian Associated Press
