A Kiwi mum accused of abusing and starving her nine children for nearly two decades to atone for their "sins" has seen her prison sentence quashed.

The 52-year-old was jailed for four years in November for what a judge described as "prolonged and sadistic" offending, but she will now be resentenced after the Court of Appeal quashed her prison term at a hearing on Friday.

The court ruled there was no apparent factual basis for the sentence imposed and it is likely a disputed facts hearing will be required before the woman is sentenced again.

Her lawyer, Phil Hamlin, has said the woman accepted responsibility for her offending, which dates back to 2000.

"Although she accepts she did wrong, she was trying to do right," he said. "Her children were the sole focus of her life."

A potential disputed facts hearing will involve Hamlin setting out the details of the case which are not accepted by his client.

The devout Christian mum, who home-schooled her nine sons and daughters, remains in custody, however, with bail to be decided by the District Court, the Court of Appeal ordered.

The Herald first revealed the allegations against the mother last year, which included starving her children, submerging them overnight in cold swimming pools, ordering them to run "punishment marathons" around a circuit, and forcing them to wear signs around their neck which read "liar".

At her sentencing, the court heard the children's father had split from his wife, was "genuinely sorry" about the abuse and wanted to make amends with his kids.

Today, the Herald on Sunday can also report his crimes.

Court documents show the father had earlier pleaded guilty and was convicted of two charges of assault with a weapon.

Two of the dad's children, aged 10 and 14 at the time, were the victims.

"Annoyed with them over their fighting indoors, [the father] made the children go outside and run around a paddock on which there was a circuit," court papers read.

During one occasion, the father stood at the side and hit the children with a metre-long piece of wood as they ran past, telling them to go faster.

When the children returned to the porch, they were told to remove their clothes. However, the young girl refused and as she left her father threw the plank of wood at her, hitting her on the arm.

The plank caused a welt and a bruise that took a week to heal.

The father appealed the District Court's refusal to grant him a discharge without conviction, but this was dismissed by the High Court in 2018.

His offending came to light during Family Court proceedings when the couple was separating, while the mother's abuse gained the attention of police in 2017 after the five eldest children had left home.

During the mother's sentencing, Judge Nevin Dawson said she was cruel to her children in a way "which simply cannot be justified".

Having raised her kids in a "conservative Christian lifestyle", she used her authority to abuse the trust of her sons and daughters, he said.

"You went far beyond what could ever be imagined as necessary for good parenting."

Six of the woman's children gave evidence during their mother's trial last year before she pleaded guilty midway through to six charges of cruelty to children and two charges of assault on a child, one of which was representative.

Further charges against the mum, who cannot be named to protect the identity of her children, were withdrawn by the Crown.

During the trial, the children told the jury of the bizarre punishments their mother would dish out.

These demeaning tasks, the court heard, included ordering the children to stand with their heads against a wall, crawling on their hands and knees for a day, and being told to eat grass "like a sheep".

Often their punishments were for small "sins" such as spilling something on the floor, the children explained.

Their mother also built the 800m circuit, with the kids sometimes forced to run nude while holding bricks above their heads. This even occurred in summer until they began vomiting and suffered from heat stroke symptoms, the court heard.

The eldest daughter, now in her mid-20s, said she continues to suffer the physical and psychological consequences of growing up under the influence of her "righteous" mother.

"We constantly lived under a cloud of her control," she said at the sentencing. "We had no privacy, we had no rights.

"I cannot see that she will have any kind of a mother's place in our lives."

She told the court she now requires hearing aids in both her ears, due to damage doctors believe was caused by being slapped across the head by her mum.

Another of the woman's now adult daughters recalled daily life as a "military-like" working day from 6.30am until 11pm.

She later learned from a doctor her daily headaches may be due to head trauma, she said.

"It is the emotional scars that impact me the most."

A date for the mother's resentencing or a disputed facts hearing is yet to be set in the District Court.