An elderly woman who suffered a heart attack during a bizarre home invasion died five months later without police taking a formal statement from her.
Officers spoke to her briefly, but said she added little of value.
However, one of her sons is unhappy about the lost opportunity to solve the mystery of what happened in the early hours of March 8.
About 3am that day, a man entered Vera Smith's Levin house and sat in her armchair in the lounge, where one of her sons, who is disabled, was staying.
The son set off his medical alarm, alerting Vera Smith and another of her sons, Paul Smith, who also lived at the Bledisloe St house.
The intruder left after a struggle with the older son, who complained of heart trouble and minor injuries in the melee. He cannot be named for legal reasons.
Vera Smith, who would have turned 89 on January 18, was also rushed to hospital, suffering a heart attack.
She returned home, but was later back in Palmerston North Hospital, where she died on August 7.
Police are investigating her death on behalf of the coroner, but Paul Smith is upset officers never took a formal statement from her about the home invasion.
"An ambulance took her away straight away. When she came home, she never heard from them," he said.
"When she was taken to hospital I can understand, but why, when she was discharged and came home, why did someone not contact her?"
A statement from police says: "There was no formal statement taken from Vera Smith, however, it is noted in the file that she was spoken to briefly by the attending officer.
"She was able to add little that would assist police with their inquiries."
Paul Smith said CCTV cameras at the house snapped the intruder and police had a suspect in mind.
Paul Smith went to the Levin police station last week to discuss the incident and said a different detective from the one originally assigned was now leading the investigation.
"The new investigation team has made contact with me and got a formal statement and I'm very happy with the way things are now progressing."
Paul Smith briefly saw the man sitting in his mother's chair, but said he didn't want to describe him in case it jeopardised the police investigation.
Vera Smith was rattled by the intruder. She was recovering when her health took a turn for the worse in April, Paul Smith said.
"I'm glad she's not suffering any more and she's resting in peace."
Paul Smith said he was thankful for the support of the doctors and staff at Palmerston North Hospital.
Police confirmed they are still investigating the home invasion and that Vera Smith had since died.
"Her death has been referred to the coroner and police will investigate on the coroner's behalf.
"The investigations are separate."
In March, police said a man and woman living at the house told the intruder to go, but he sat down in the lounge instead.
"After a small struggle with the occupier, the intruder left the property, taking nothing with him," a police spokesman said.
Police were then investigating forensics and CCTV footage from the house.