A man jailed over the death of his 24-week-old son should face a customary "payback spear", family say.
Kozan Samuel Thomas Ware was sentenced to jail on Thursday for killing Adrian Joshua Wommie Ware who sustained a head injury likely caused by blunt force trauma and shaking.
The now 35-year-old earlier pleaded guilty to manslaughter as a domestic violence offence, after originally being charged with murder.
He was sentenced in a packed courtroom with staff ensuring family members and supporters of Ware and the baby's mother were seated separately.
Adrian was declared dead after emergency services responded to a call that the baby had been found unresponsive at a home in Cleveland, southeast of Brisbane, on March 28, 2017 about 8.50am.
Ware was arrested more than a year later later.
Speaking outside court after Ware was sentenced, Adrian's uncle, joined by the baby's mother, said the family wanted their justice too.
"We feel that he should be facing the spear when he get out of jail ... a payback spear," he told reporters.
"To be able to serve our justice we want him to face a spear ... because we don't feel that any justice has happened here at all today."
He said Adrian's mother had been "living through hell".
Ware and Adrian's mother lived together intermittently, but about five days before the baby's death she failed to return home after saying she was going to the RSL, prosecutor Caroline Marco told the Brisbane Supreme Court on Thursday.
"She was sick of being left at home" and having to look after the baby, Ms Marco said.
Until that time she had been the baby's primary carer with Ware never having looked after the child alone for long.
Ware received money from his sister to buy groceries and struggled emotionally with the baby teething and playing up, the court heard.
He also reported Adrian's mother missing, receiving a visit from police who described the house as having a strong odour like rubbish.
He sent a series of text messages to his sister and a woman he had been seeing including one in which he said Adrian could not be pacified.
"He said that Adrian would not stop crying and he was going to end up killing the kid soon," Ms Marco added.
Ware smoked marijuana the day before Adrian's death and later sent a message containing 27 screaming or crying face emojis.
At 2.44am he wrote "help me" in a text, the court heard.
Ware started screaming when he couldn't wake Adrian later that morning.
He phoned his sister, telling her the baby was cold and blue.
Ware was in a "very distressed state" when paramedics arrived and later spoke to police, but had not provided an explanation for the injury that caused Adrian's death, Justice Helen Bowskill said.
An autopsy found the cause of the head injury - which occurred between two hours and 48 hours before Adrian's death - was "blunt force trauma and shaking, potentially in combination", she added.
Adrian also had a cut to his upper lip that may have been caused by a dummy being pushed forcefully into his mouth.
"It is just the most tragic circumstance for everybody concerned, Justice Bowskill added.
But she said Adrian's death had come about because of "accumulated frustrations or a single application of frustration" when he was unexpectedly left to care for the baby.
She sentenced Ware to nine years behind bars, ordering he be eligible for parole after serving 40 per cent.
Ware has already served more than two years behind bars.
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Australian Associated Press