A friend of Margaret Bain has told a High Court jury she was told Robin Bain suffered from depression many years before the couple died.
Joanna Dunn was giving evidence in the retrial of David Bain in Christchurch on Thursday.
The Crown says David Bain, 37, killed his parents Robin and Margaret and siblings Arawa, Laniet and Stephen at the family's house in Dunedin on 20 June 1994.
The defence argues Robin Bain was depressed and unstable, and killed the family present in the house before shooting himself.
Evidence during this trial has conflicted regarding Robin Bain's mental health.
Robin Bain's family say they did not know of any depression, but some of his work colleagues have given evidence that he was deteriorating.
Ms Dunn told the court that, although she did not see any evidence of depression, she was told by Margaret Bain that Robin Bain was depressed and getting worse.
The court was told that conversation was in 1978, 16 years before the killings of the Bain family.
Ms Dunn said before David Bain's first trial in 1995 she tried to tell police what Margaret Bain had told her, but they were not interested.
"I was concerned that Robin's depression had undulated and not really been cured and it might have had an effect on him."
Daughter was afraid of father - witness
Earlier, a defence witness told the court that the accused's sister Laniet Bain was afraid of Robin Bain.
A witness, who was living in the same boarding house as Laniet Bain in early 1994, said on one occasion she approached him to talk about her family life.
At the time, Laniet Bain was working as a prostitute and the witness, who has name suppression, says she told him her pimp was threatening to expose her to her parents.
The witness said Laniet Bain also told him she was fearful of going near the Bain family house and her father, whom she said had touched her inappropriately.
Laniet Bain also told the witness that she was jealous of David Bain because their father would take him on hunting and fishing trips.
The witness said it was the only time Laniet Bain spoke about her troubled home life.
Evidence on alleged noise from body
Ambulance officer Robert Cooper attended the scene of the killings told the court on Thursday that bodies can continue to make noises up to an hour after death.
David Bain told police he heard a gurgling noise from Laniet Bain's room when he came back from his paper round that morning.
The Crown says Laniet Bain must have been alive to make the noise - and it was a sound only the killer could have heard.
But Mr Cooper told defence lawyer Michael Reed, QC, that bodies can sometimes make noises, including groans or gurgles.