The Supreme Court of Victoria heard earlier that Malka Leifer used one student's abusive home life as a way to groom and then sexually abuse her over several years.

It was alleged in evidence on Thursday that four people once visited and harassed the student's older sister in London to pressure her to pressure other family members to drop the "charges" against Mrs Leifer.

That former student of the Elsternwick school is suing it for damages stemming from abuse she allegedly suffered at the hands of Mrs Leifer.

Justice Jack Rush heard this week that a member of the school's committee arranged plane tickets to enable Mrs Leifer to leave Australia within two days of being sacked in 2008.

She was arrested in Israel in August last year and extradition proceedings are underway to return her to Victoria to face charges.

Christopher Blanden​, QC, for the school, said on Thursday it was not the defence case to "quibble with or question" the evidence of the former student and what happened to her, but that the issue was the "vicarious or direct liability" of the school.

Mr Blanden's cross-examination of her did not touch on her allegations and he did not ask any questions of her sisters, who all grew up in an ultra-orthodox Jewish community.

The court heard earlier that the former student's abuse started in 2002, when she was 15, and as a result she had suffered flashbacks, nightmares, persistent depression, post-traumatic stress disorder and at one point was suicidal.

Now 27, she told Justice Rush she was brought up in a family dominated by her physically abusive mother and that Mrs Leifer offered to help her.

She agreed with her barrister Dyson Hore-Lacy, QC, that the indecent assaults began by Mrs Leifer touching her clothes, thighs and back and then knees, to the top of her thighs, stomach, under her bra and breasts.

She "seemed to be touching me everywhere", she said.

One of her sisters said in evidence that Mrs Leifer was a "very upstanding person" who everyone trusted, looked up to and who "charmed everyone pretty quickly".

Mrs Leifer was "very touchy-freely", which was unusual given the sisters' strict upbringing, and had "groomed" the witness in year 12 and then began sexually assaulting her.

She told Mr Hore-Lacy she had been too scared to talk about what happened, but when approached in August, 2008, she told a woman "it was all true".

She agreed that Mrs Leifer then pulled her out of a class and "begged me" to tell her "what was going on" but she did not answer her.

It was the last time she saw Mrs Leifer, who soon after "disappeared" to Israel.

Questioned by Justice Rush, she said "you do not dare" to speak out or you would be ostracised.

A third sister, who had also made a statement to police, said Mrs Leifer sexually assaulted her between 2006 and 2007.

Mary Mass, a counsellor and advocate, agreed with Mr Hore-Lacy that the childhood background and naivety of the principal witness of the alleged sexual abuse was significant to the later health issues she faced.

Ms Mass said a lack of knowledge of sexual matters would make her "more vulnerable to any form of sexual abuse".

Questioned by Mr Blanden, and based on what her treating psychiatrist is expected to say in evidence, Ms Mass said the woman had "recovered enormously" between 2011, when she was first treated, and last December.

Asked if she agreed that the woman had been compliant with all treatment and had shown insight, Ms Mass replied: "She definitely wants to feel better."

The hearing continues.