The father of four-year-old Tyrell Cobb has said his son's mother and her partner should "rot in hell" after the young boy died as a result of a blow to his stomach.
Jason Cobb told A Current Affair on Monday the pair were "disgusting people".
"If they're responsible, they can rot in hell," he said.
The father was shattered by footage of Matthew Scown walking free from court after serving two years and eight months behind bars smiling and laughing.
"That's like a slap in the face, basically," he said.
"If you want to smile like that, have some remorse, but he had none."
Tyrell's mum Heidi Strbak, 34, was sentenced to nine years after pleading guilty to manslaughter. The young boy had a total of 53 bruises and 17 abrasions on his body at time of death but his mum claimed she didn't land the fatal blows.
Scown also pleaded guilty to manslaughter on the basis of not taking Tyrell to the doctor, but argued he was not responsible for the fatal blows to his stomach.
"They can argue he said, she said; it doesn't matter. They were both there, they're both responsible," Mr Cobb told ACA.
"If she gets what she deserves, I'll be happy. She can go to jail and I'll be happy," he said. "Not happy, but happy for Tyrell."
Mr Cobb broke down as he remembered his son as a "happy little boy, playful, cheeky".
During Ms Strbak's sentencing Monday, Jutice Peter Applegarth said: "You made a terrible error of judgement for not getting treatment for this sick boy."
"The last hours of his life must have been miserable and painful."