The father of a teenager who was murdered in 1977 has told a court his wife was never the same again after their daughter's death.

Morain Scott, 84, said the death of his daughter Helen Scott marked the start of his wife Margaret's ill health, while he has lived with the loss for over 30 years and has "just kept going".

Mr Scott was giving evidence on the second day of the trial of Angus Sinclair, 69, at the High Court in Livingston.

Sinclair has pleaded not guilty to assaulting, raping and murdering Ms Scott and her school friend Christine Eadie, both 17, between October 15 and 16, 1977, between the World's End pub in Edinburgh and locations in East Lothian.

Mr Scott was asked to describe what happened on the evening of October 15 when his daughter failed to return home from a night out, and the events of the following day when her body was discovered and identified.

He said his daughter had told her mother, who died in 1989, that she planned to go out with friends straight after finishing work at a tartan shop on Princes Street in Edinburgh.

"In the morning she was going to her work and she said to her mother, 'I am going straight out with Jackie and I am meeting Christine later', she said, rather than coming home first," Mr Scott said.

Asked by Lord Advocate Frank Mulholland, prosecuting, about what happened later that evening, Mr Scott said: "I thought she would be back at her normal time - 11.30ish - as she always had been."

He said that by 11.30pm his daughter had not come back to the family's home in Swan Spring Avenue, in Comiston, Edinburgh.

"I went up to bed and my wife stayed up all night," he said.

Mr Scott said his wife heard the phone ring between 11.30pm and 12am, but when she went to answer it, it had stopped.

Mr Mulholland asked if he and his wife were worried when their daughter had still had not returned the following morning.

"Very much so," he replied.

After attempting to contact his daughter's friends Jackie Inglis and Ms Eadie, the court heard Mr and Mrs Scott reported their daughter missing to the police.

Later on October 16 the couple heard radio reports of two bodies being found, one near Aberlady and another near Huntington, both in East Lothian.

"We just sat down and thought it surely can't be Helen and Christine," Mr Scott said.

He told the court police officers later visited with items of Ms Scott's clothing, including a new coat she had bought a few days previously. Mr Scott later identified her body.

Asked by Mr Mulholland about how his daughter's death had affected the family, Mr Scott said: "My wife, she was never the same... as far as I was concerned it was the start of her health going down.

"From my own point of view I have had to live with it for over 30 years and I have kept it to myself because I didn't want to bother anyone else.

"I have just kept going. Simple as that."

Mr Scott described his daughter to the court as "a shy girl" who had ambitions of becoming a children's nurse, and was attending evening classes.

During cross-examination, Ian Duguid QC, defending, asked Mr Scott about his daughter's social life.

He said there seemed to be some evidence that Ms Scott had had about 10 alcoholic drinks, including wine, vodka and whisky, during the evening of October 15.

"If she had about 10 different alcoholic drinks on the night, as far as you are concerned that would be out of her character?" Mr Duguid asked.

"Yes," replied Mr Scott.

"The type of character she was in the company of her pals, were you able to see that, or did you not witness that personally?" Mr Duguid asked.

Mr Scott said: "I only saw her with pals if they visited the house."

Sinclair has submitted three special defences of incrimination - blaming his brother-in-law Gordon Hamilton, now dead; alibi - saying he was fishing on the banks of the Firth of Forth near Cockenzie power station at the time; and consent to sexual intercourse.

The trial, before judge Lord Matthews, continues.