Warning: graphic content.
Auckland man Phillip Welsh has been sentenced to nearly six years in jail over the death of baby Malcolm Bell.
Welsh pleaded guilty to manslaughter, admitting his role in Malcolm's death, on the eve of his scheduled jury trial.
More than a year had passed since the death of the baby boy, who was 17 months old.
"How could you deny any wrongdoing for so long and then suddenly admit your guilt but only to manslaughter?" the baby's mother asked Welsh in court.
'You killed my baby'
Reading a statement to the High Court at Auckland, Malcolm's mother, Savanna Bell, said she was haunted at night by visions of her son's "little body" being smashed.
"You're a liar, a coward, a monster," she told Welsh.
"You killed my baby," she said, adding that in her opinion that was murder.
According to the summary of facts, on June 23 last year Welsh threw Malcolm with significant force towards a couch while more than a metre away.
Malcolm hit the back of the couch, the wooden frame of which was thinly covered, and fell to the floor.
"He was immediately rendered unconscious and did not move," Justice Christian Whata said.
At 7.32pm, Welsh had called Bell, saying Malcolm was having a seizure and needed an ambulance.
She recalled in court how she had run faster than she had ever done before, desperately trying to get home.
"The world around me was spinning out of control. I just had to get to my son."
As she ran, she dialled 111 and spoke to an ambulance call-taker.
When the ambulance arrived at 7.43pm, paramedics would describe the unresponsive boy's breathing then as "slow and laboured".
Bell said Welsh had failed to tell the truth about what happened and she sometimes wondered if her boy would have received the help he needed if Welsh had told the truth.
She later watched Malcolm slip away in hospital, the court heard.
Bell remembered her precious baby being born a happy, bonny boy.
She recalled happy outings together in Auckland and how Malcolm had liked to feed ducks.
She finished her statement by saying she believed Welsh deserved a life sentence.
'Malcolm can never be replaced'
Malcolm's maternal grandmother, Sophie Pokai, told the court her heart had dropped when she was told he had been admitted to hospital.
"Why are the police here?" she remembered thinking.
She sat at Malcolm's bedside, unable to take away his mamae (pain), she said.
"Children and grandchildren are meant to bury their parents and grandparents, not the other way around."
Welsh had "broken the circle of my whānau".
"He has taken one of my taonga away from me. Malcolm can never be replaced."
In sentencing, Justice Whata took into account Welsh's troubled upbringing and that information before him showed Welsh had a low risk of reoffending.
Justice Whata said there were three seriously aggravating factors in the offending.
Firstly, there had been "extreme, indeed brutal violence".
"You threw Malcolm with such sufficient force it caused a major head injury."
The medical notes observed that if the child had survived he would have suffered blindness, Justice Whata said.
Secondly, Malcolm was "utterly vulnerable" and there had been a breach of trust.
Third was a "deliberate" concealment of the offending from medical officers at the time.
For manslaughter, Welsh was sentenced to five years and 11 months in prison.
The judge set a minimum non-parole period of half that term.
After the sentencing, Detective Senior Sergeant Geoff Baber said Malcolm's life was "cruelly taken from him".
"He was a vulnerable little boy and he should have been safe in his home."
The Herald has previously reported that Oranga Tamariki had been contacted with concerns about the welfare of Malcolm before he suffered fatal injuries.
After his death the agency initially declined to comment before an Auckland manager then said they had been working to support to him and his whānau before his death.