A friend of Laniet Bain has told the High Court at Christchurch that when she first saw David and Laniet together she thought they were a couple, not brother and sister.
David Bain is on trial, accused of the murders of Laniet and the other four members of his family at their Dunedin home in June 1994.
The witness, who has name suppression, told the court Laniet spoke warmly about the rest of her family but her "attitude was very strange about David".
Laniet referred to him as, "My David", and after breaking off a minor relationship the witness had with David, Laniet told her that she had "hurt my David".
Laniet told her that David was jealous of her relationships with men.
When she last saw Laniet she mentioned David "again and again and again", she said. Laniet was scared of upsetting him and was worried about what he thought about what she did.
Another friend said David Bain was a different person when he was on stage. He was confident and egotistical in a way in musical productions, but off stage he was mild, meek and geeky, she said.
She found the family friendly but odd, and said that when she went to the family home in Every Street, Dunedin, she was not allowed to go into the den, which was the first room to the right inside the front door.
This was the room where David's father Robin Bain was found dead in June 1994.
A couple also gave evidence that Robin Bain and his wife Margaret invested in their motel business when the Bain family sold a house in Dunedin. They had rented the house out during their missionary work overseas, but sold it during a visit home.
An accountant told the 29th day of the trial that about the time of the murders, the family had $65,109 invested.
Earlier a Dunedin optometrist told the court he had sought to change the evidence he presented to the first murder trial of David Bain, prior to the trial.
Gordon Sanderson said he was given a frame for glasses and two lenses by the police, and asked to match them to the prescriptions for the glasses for members of the Bain family.
Mr Sanderson said the frames were a normal male design and the prescription in the lenses were close to David Bain's prescription.
However, a week before the trial Detective Sergeant Milton Weir showed him a photograph of David Bain's mother Margaret wearing the same glasses and he realised they were hers.
He asked that his statement be changed, and was assured it would be by Mr Weir.
At the trial he partly read his statement, and realised the change hadn't been made.
He answered questions and was waiting for the change to come up, but when it didn't he decided that the jury had been told of the change of evidence.
Mr Weir has denied the allegations.
Mr Sanderson said that David Bain would have been able to see very well with his mother's glasses as their prescriptions were similar, but they would have made Robin Bain's eyesight worse and would be no use to him.
The trial has been told that the frame and one lens were found in David Bain's bedroom on the morning of the killings, but the other lens was found in the bedroom of 14-year-old Stephen Bain who had been killed after a struggle.
The trial is before Justice Graham Panckhurst and a jury.
