Mothers are leading their families away from Orthodox communities to Reform, often prompted by concerns over their daughters’ batmitzvahs, according to Rabbi Laura Janner-Klausner, Senior Rabbi of the Reform movement in the UK, and its leading spokesperson.

“We are steadily growing in numbers,” she says, “led by women who are coming from Orthodox communities who don’t want to compromise for themselves or for their daughters.”

She says many families make the move in the run-up to a batmitzvah, disappointed with what is on offer to girls in many Orthodox communities.

“We give them ownership of their Judaism,” she says, adding that more Hebrew and singing in Reform services also makes the transition easier for formerly Orthodox families.

What about the growing popularity of Masorti? It’s a north London phenomenon, she says, and Masorti are Orthodox in all but name.

She has been the voice of Reform for five years now, and predicts that the drift from Orthodox to Reform will continue apace, fuelled by the Orthodox authorities’ attempts to curb moves to increase women’s roles in prayer and community leadership.

For Rabbi Janner-Klausner, who grew up in the United Synagogue but left for Reform after finding her own batmitzvah a complete disappointment, Reform offers women and girls a space where they do not have to compromise or change who they are when they walk into a synagogue.

She is about to start two groups at her home, one teaching Talmud to young women leaders, the other teaching about the “false obstacles placed in front of women in the name of halachah”. Knowledge is power, she believes.

She is “overjoyed” to see women’s responses to being given the same opportunities as men.

“If you stick a woman in front of a Torah there is no going back. Women often weep to be so near to a Torah. In fact, I have to move the scroll away sometimes so it doesn’t get wet. But the Torah is all of our inheritance.”

The day we meet she had delivered Radio 4’s Thought for the Day, talking about stress. She described how organisations learn from applying stress tests to their processes, concluding: “I believe that identifying failings under stress can strengthen us.

“If we’re supported and can properly internalise our mistakes, they can be the beginning of a process of repair and resilience building.”

Resilience has been much on her mind recently, as the subject of her first book (she has contributed to others, but this one is all hers). The manuscript has just been delivered to the publishers, the first third of the which is “very autobiographical”, the rest offering more practical advice about dealing with difficult times.

This, of course, is a subject on which Rabbi Janner-Klausner and her siblings are experts, their own stress test being the accusations of sexual abuse made against their father Greville; accusations which have not disappeared with his death.

The accusers are suing the late peer’s estate for damages and the case is due in court again next week.

Much has been written about the case, not least in the JC, and as Rabbi Janner-Klausner says, the many words that the family could say about it can be boiled down to three: Dad, Innocent, Love.

Writing the book has given her a chance to “channel my trauma,” she says. She worked with journalist Gabriel Pogrund, finding it easier to talk than write it herself: “Obviously I am an extrovert!”

Her debt to and love for her father shines throughout our conversation. His political career shaped her, he taught his children to look people in the eye and talk to everyone in the room.

She jumps up to show me an election poster she found: Vote Janner, it says in giant red letters. She’s planning to frame it.

“He taught us to fight for those who are marginalised and disadvantaged,” she says, adding that her parents would have been pleased and proud at the way she and her siblings have come together. She had already spoken to her brother Daniel four times that day.

The community has been very supportive, she says, tears welling in her eyes as she mentions the “kind, brave and wonderful” Community Security Trust who protected the whole family.

As the abuse continues to roll in, her staff vet her emails and try to protect her from the worst examples.

For someone who clearly fizzes with energy, the obvious escape route is into work — this time voluntary.

She has been working with the Muslim community in Bradford to create a new programme to combat prejudice by tackling the Israel-Palestine conflict head on, an initiative designed to prompt “difficult conversations,” led by two facilitators, one Jewish, one Muslim. The hope is that the programme will expand, going into schools, colleges and prisons.

Traditional interfaith work is not enough, she says, pointing out that support for the Palestinian cause is “a catalyst for cohesion in the Muslim community,” which gives it increased significance to many.

“It’s an incendiary subject. We are starting by questioning assumptions, sowing seeds against hatred by proxy.”

It is important that the scheme is not linked to the government’s controversial Prevent strategy, she says and the organisers are hoping to gain the backing of Sajid Javid, the Communities Secretary.

Again the conversation comes back to her father. “I’m continuing Dad’s legacy of cross-communal work,” Janner-Klausner says.

Sometimes, she finds it easier to work with Muslim groups than with mainstream Orthodox Jewish authorities, although she stresses that her door is always open to co-operation.

She says of Chief Rabbi Ephraim Mirvis that they have a “cordial but not a working relationship,” and that clearly frustrates her.

“I would love to work together in areas such as interfaith and antisemitism, combating BDS, and that is not happening. It is a great shame.

“We need to look at what happens within other faiths. We have a duty to look after Jews together. For the sake of Klal Yisroel, we need to be more co-ordinated.”