DARRAGH family siblings are in dispute over comments made to the media about the death of their mother Marie at Ballina's St Andrews Nursing Home last month .
Mrs Darragh, 82, and fellow resident Isobella Spencer, 77, were found unconscious in their beds about 7am on May 10 by nursing home staff and were pronounced dead shortly after.
Police are now treating the case as a double murder.
On Thursday, Mrs Darragh's daughter Charli told The Northern Star if she had moved her mother from the home 24 hours earlier she would still be alive today.
But Mrs Darragh's son, Jeff, says that is not correct.
Jeff said his sister Charli, whose real name is Judy, broke a family agreement made at their mother's funeral not to speak out about her death until the police investigation was finalised.
"I have spoken to the police involved in the investigation and they said when they get all their ducks in a row they will make an arrest," Mr Darragh said.
He said his sister's claims were motivated by "personal spite against the family".
Before Mrs Darragh was put in the nursing home in 2011 she was a smoker, was neglecting to eat and was put into hospital weighing only 48kg.
Then the family managed to get her into St Andrews, which, Mr Darragh said, turned her life around.
"They looked after her, got her to quit smoking and got her up to 78kg and it was wonderful," Mr Darragh said.
"She was in real good health after that. She was brilliant, better than she had ever been.
"Mum was so happy at St Andrews, she loved it there."
Mr Darragh said he hoped people around Australia disregard comments made in the media "by other distraught family members".
"I wish she would just let police do their job and let justice be served," he said.
A relative of Isobella Spencer, who did not want to be named, said St Andrews had done "a wonderful job with Isobella".
"Isobella was a very introverted, dignified lady and her death has been very undignified," the relative said.
A State Crime Command spokesman said police were still waiting on forensic test results from both autopsies.