Daughter supported father's wish to die

The daughter of a man who died from an overdose of a euthanasia drug says she supported his request for help to die.

Seventy-one-year-old Graeme Wylie had been diagnosed with Alzheimer's disease before he died from an overdose of euthanasia drug Nembutal in 2006.

His partner, 51-year-old Shirley Justins, is standing trial in the New South Wales Supreme Court for his murder.

Mr Wylie's daughter, Nicola Dumbrell, has told the court around the time her father was diagnosed he complained of dizziness, lost interest in his hobbies and sometimes just nodded during conversations with her.

She said when Shirley Justins asked her to write a letter of support to the Swiss mercy killing organisation Dignitas to help her father take his own life, she agreed.

She also said Shirley Justins had discussed her father's will with her.

The trial continues.