The father, 74, who cannot be named for legal reasons, is facing trial in the ACT Supreme Court on 16 charges of child sexual abuse on four victims dating back to the 1970s and 1980s.

He has pleaded guilty to three charges. The pleas of guilty relate to an incident involving a daughter in which he touched her while she was pretending to sleep when she was about 6 or 7.

The other charges relate to an alleged incident against the same daughter, different alleged incidents regarding a second daughter, and others on two girls who had been dropped at the family day care run at the family home by the man's wife.

On Tuesday, a school friend of the first daughter gave evidence.

She told the jury that her friend's family and her family had been members of a lay Christian support group in Canberra in the 1970s and 1980s.

Under questioning by prosecutor Trent Hickey, the woman said when her friend was about 17 or 18 she had disclosed to her the sexual abuse at the hands of her father.

She said the daughter had spoken of her mother's reaction: that she should forgive her father so that everyone could move on.

"She was really upset. She felt ... betrayed. That there was no understanding of what it was like for her. There was this notion that forgiving was forgetting, and she couldn't forget," she said.

Under cross-examination by defence barrister Amanda Tonkin, the woman said she had spent many nights at the family's home and never seen inappropriate conduct by the woman's father.

The court also heard that in the year or so after the woman's disclosure of sexual abuse, the daughter's friend moved in with and was cared for by the family for several months.

The daughter had earlier finished giving evidence via videolink.

A senior member of the church group and mentor to the daughter also gave evidence on Tuesday. She said when the daughter was about 18, she had disclosed the sexual abuse to her.

The trial continues.