The man accused of murdering five members of Sydney’s Lin family sexually abused another female family member after their deaths, a court has heard.

Prosecutor Mark Tedeschi told the New South Wales Supreme Court Robert Xie had three motives for murdering his brother-in-law Norman Lin, Mr Lin’s wife Lily, their two children and Lily’s sister Irene in their North Epping home.

The court has heard the family members were bashed to death at night with a hammer-like object in 2009.

Mr Tedeschi said Robert Xie resented his brother-in-law because he thought Norman Lin was given preferential treatment by family elders and wanted control of his assets.

The court heard that after newsagent Norman Lin was murdered, Robert Xie, through his wife Kathy Lin, got control of the newsagency.

“The accused through his wife made a concerted effort to wrestle control of the assets,” Mr Tedeschi said.

The prosecutor said Robert Xie also had a sexual motive.

He said he made sexual advances towards a female relative before the murders and sexually abused her from September or October 2009 until he was arrested.

The court heard the female relative only came forward with the information in May this year.

Mr Tedeschi said the abuse often occurred twice a week.

He said the crown case was that the accused had a sexual desire for the female relative that was so great it made him prepared to take the risk of abusing her while other relatives were in the same house.

He said at other times the abuse was when they were alone. He said the relative will give evidence at the trial.

The trial continues.