Baby Isaiah Neil was just 8 months old when he was left asleep in a car at home in Rūātoki, near Whakatane, on November 2, 2015.
At least five visitors to house where a baby was trapped in a hot car had the chance to save him, but none of them knew the infant was in the vehicle.
Isaiah Neil was just 8 months old when his mother Lacey Te Whetu and grandmother Donna Catherine Parangi left him asleep in a car at their home in Rūātoki, near Whakatane, on November 2, 2015.
Parangi is on trial at the High Court in Hamilton for the manslaughter of her grandson. Te Whetu and Isaiah's father Shane Neil have previously pleaded guilty to manslaughter.
Isaiah was found hot, limp and lifeless by Neil at 3.30pm, about three hours after Te Whetu and Parangi arrived home from a drug run to Kawerau, where they bought synthetic cannabis off a cousin.
The pair left Isaiah sleeping in his car seat and went inside to smoke the drug before falling asleep. Neil also smoked the synthetics that day and fell asleep too.
The former girlfriend of Parangi's son Marcus Te Whetu, Felicia Riini, told the court today she and Marcus went to his parents' house that afternoon, about 2.30pm, to collect something.
Riini told the jury of eight men and four women she did not get out of the car, and that the couple only stayed five minutes. They were not aware Isaiah was in the car on the warm Spring day.
However her evidence contradicted that of Marcus and two Kohanga Reo employees who dropped off Isaiah's two older siblings at 3pm that day.
Marcus earlier told the court he was at the property for about an hour that afternoon washing his car. He never looked in the blue Honda station wagon that Isaiah was in.
The two women who dropped off the older children also noticed the car but did not know a baby was inside.
They left after Neil came out of the house to retrieve the children from the van, with one witness testifying that Neil appeared "normal".
The court also heard the statement of an acquaintance who said he called around the house that afternoon to collect a weedeater, and noticed the parked car, but did not look in it.
The man, Paul Daniels, said he did not notice whether the windows were open or shut.
It meant five adults were outside the house that afternoon and another four were inside - Te Whetu, Parangi, Neil and Parangi's husband Santa Te Whetu - but none came to the rescue of the infant.
In his statement to police, Daniels said he went back to the house later that night when the ambulance arrived, after 6.30pm, to see what was happening.
"Shane was acting all weird. He didn't seem concerned with what was going on. Isaiah was in the back of the ambulance. Lacey and Donna were hanging around the back.
"They seemed in shock and upset. Santa was standing nearby and Shane was just wandering around."
Meanwhile Riini told the court Neil was "no father" to his children.
The early childhood worker said she and Marcus were often in charge of the three children because Lacey and Parangi were addicted to synthetic cannabis.
Riini said she lived at the house in Rūātoki on and off with Marcus and was often looking after not only the children, but Te Whetu and Parangi too.
"Lacey was a lovely mother. She always catered to her children's needs. Food, clothes, nappies," Riini said.
Under questioning from Crown prosecutor Richard Marchant, Riini admitted Te Whetu was only a good mother when she was not stoned, and that Parangi was a good grandmother.
She said if the children were crying or wanting Neil's attention he "just walked straight past them" or "walk away".
Riini said Neil was experimental with synthetic cannabis, and did not smoke it regularly.
Yesterday defence counsel Susan Gray pointed to asphyxiation or abuse as the potential cause of Isaiah's death and not heatstroke.
Through questioning of Te Whetu, Gray showed the 29-year-old mother was not concerned when Neil handed her a hot and sweaty Isaiah at 3.30pm.
She was not concerned when the baby did not take a bottle and assumed he was in a deep sleep.
Te Whetu testified Isaiah was only in the same bed as her and Neil for a few minutes before she placed him in his cot, where there were several blankets.
Gray asked if Isaiah's preschool-aged brother jumped in the cot but Te Whetu said he had never done that before.
It wasn't until she woke again at 6.30pm that Te Whetu discovered Isaiah not breathing in his cot and rang 111.
Yesterday Marcus testified that he went to the house on the morning of the baby's death to "check on my nephew to see if he was alright".
He discovered Isaiah lying on a mattress in the lounge, with a runny nose and full nappy.
The court also heard Isaiah, who had been sick with bronchitis, had a large bruise and abrasion on his stomach when paramedics arrived that night. The baby also had an adult bite mark on his body.
Ambulance officer Linda English told the court Isaiah was warm when she arrived at the house to find a man giving mouth-to-mouth to the baby and Parangi squeezing the outside of his chest in an attempt at compressions.