WARNING: This story details the death of a young girl and may be distressing for some readers.

While an infant’s death remains unexplained, a coroner has examined the possibility the child’s older sibling may have played a role in the tragedy.

Today, Coroner Heather McKenzie released findings saying the girl’s death may have resulted from accidental or deliberate smothering, a sudden unexpected death in infancy (SUDI), or a medical event.

The child was the youngest of several children. The findings detail a series of interactions with Oranga Tamariki, health services and support agencies in the days before her death.

Concerns before the death

The mother told police and other agencies that her preschool-aged son had been showing violent behaviour towards her, the infant and an older sister.

She said she was scared he would try to harm the infant and that when he became angry or frustrated, he would shout, hit out and throw or slam objects.

The woman’s mother told police her grandson had been acting differently and had been aggressive before his sister’s death.

Kindergarten staff, family members and other witnesses also described challenging and unusual behaviour from the boy.

Agencies step in

The mother called emergency services five days before the girl’s death after waking to find the boy lying on top of the infant.

She was found active and responsive.

The mother told police that about two hours later she heard muffled screaming and ran into a room to find her son on top of the infant again, wriggling.

She pulled him off and found her daughter “pale blue, just lethargic”.

Emergency services were called again, reporting the infant appeared less interactive and paler than earlier.

The girl was taken to hospital where she was assessed and appeared normal.

An emergency social worker was consulted before discharge amid allegations the brother had lain on the infant, causing her to turn blue, and that her mother had reported similar incidents on multiple occasions.

The hospital emergency department and Hato Hone St John filed a report of concern with Oranga Tamariki when the infant was discharged.

The mother met with Oranga Tamariki and whānau support workers that day to develop an interim safety plan.

Oranga Tamariki stepped in to support the family. Photo / NZME

It was agreed the boy would stay overnight with his grandmother until a face-to-face meeting the following day.

The mother called emergency services again the next day after the infant failed to wake for a feed and was difficult to rouse.

She was taken to hospital, where examinations returned results within normal limits.

Meanwhile, an Oranga Tamariki social worker contacted the mother and a whānau services worker to arrange a face-to-face meeting to review the safety plan.

The mother said her sister was staying with her and updated the social worker about the hospital admission.

They agreed to meet after the infant was discharged.

Three days later, the social worker contacted the mother again and was told the infant had been discharged from hospital that day.

A friend who looked after the infant early that afternoon noticed bruising around her nose and beneath her eyes, which she believed she had first seen at the hospital four days earlier.

Coroner Heather McKenzie was unable to make a finding on the cause and immediate circumstances of the infant's death. Photo / Tara Shaskey

The mother told police she was at home with the infant and the boy that night and put the girl in her bassinet in the lounge about 10.30pm.

She slept on the sofa and the boy slept in a bedroom. She later told police she chose the sofa because she was worried about the infant, and it was warmer near the fire.

At 2.30am, she fed the girl, returned her to the bassinet and went back to sleep.

When she next awoke, the infant was asleep but looked pale.

The mother told police she thought nothing of it and instead interacted with her son, who had been playing in his room, giving him breakfast and doing “what I needed to do”.

She said she was not aware of her son having been in the lounge and that no one else had been at the house that day.

The mother later went back to sleep.

When she woke again, she noticed the girl was not breathing. She phoned an ambulance and her friend.

The infant could not be revived and was pronounced dead.

Coroner unable to determine cause

Coroner McKenzie said a forensic pathologist found no infectious, traumatic, toxicological or underlying natural cause of death during the autopsy.

However, two possibilities warranted consideration, she said.

The first was sudden cardiac death associated with underlying cardiac conduction abnormalities.

Those abnormalities can be present from birth and may cause a sudden, potentially fatal heart rhythm disturbance at any age.

Many leave no signs that would allow a diagnosis at autopsy.

The second possibility was the death resulted from asphyxiation or smothering by a sibling or another person.

Given the incidents described in the days before the tragedy, the pathologist advised the possibility the sibling was in the same room at the time of death could not be ruled out.

“Similarly, the scenario that someone other than this young sibling was involved in any smothering attempts should also not be discounted,” the pathologist said, as reported in the findings.

“However, it should be reiterated that no injuries or other positive findings to support this mechanism were found at autopsy.”

On the available evidence, Coroner McKenzie said she could not make a finding on the cause or immediate circumstances of the infant’s death.

“This is because of the various open possibilities, as well as because on the evidence before me, the death was not witnessed.

“This second factor fundamentally means that even if other possibilities had not been brought to light by the evidence, I still could not make safe findings about the cause and circumstances of the death because no one saw, or has told police, what happened.”

Al Williams is an Open Justice reporter for the New Zealand Herald, based in Christchurch. He has worked in daily and community titles in New Zealand and overseas for the last 16 years. Most recently he was editor of the Hauraki-Coromandel Post, based in Whangamatā. He was previously deputy editor of the Cook Islands News.

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