A retired probation worker who scalded her step-daughter to death half a century ago has been jailed for 12 years after her crimes were finally uncovered.

'Sadistic' stepmother Janice Nix, 67, whimpered and put her hand over her mouth as she was jailed after being convicted of the manslaughter of Andrea Bernard, the five-year-old daughter of her new boyfriend, Desmond Bernard senior.

Nix was aged between 18 and 19 at the time and meted out 'cruel and gratuitously degrading' so-called 'punishments' on Andrea and her older brother Desmond junior.

The 'cycle of violence' culminated in forcing the terrified little girl into a bathtub of scalding water at their home in Thornton Heath, south London, in 1978.

Andrea died of her injuries in 'excruciating' pain the following month. But Nix’s crime went unpunished for nearly 50 years because police initially believed her alibi that she was in the back garden at the time, after Nix forced terrified Desmond to support her story or face further violence.

It was only in 2022, after Nix published airbrushed memoirs in which she described her luxury lifestyle as a drugs kingpin before finding redemption mentoring young people, that Andrea’s older brother told police Nix had lied and Andrea’s death was not a 'tragic accident'.

Sentencing Nix for manslaughter and child cruelty, judge Mr Justice Lavender said: 'You took Andrea's life and you caused grief and misery to her family, as her mother Angela and brother Desmond have explained so eloquently.

'You ran the bath, you knew how hot it was, you told Andrea to get in the bath, she said it was too hot.

'But you put or made her get in. You heard her screams. At the very least the risk ought to have been obvious to you.'

Nix denied manslaughter and a separate charge of child cruelty relating to Mr Bernard - Desmond junior - who was three years older than Andrea.

She told the court she had no explanation for Mr Bernard's decision to come forward, other than a spurious reference to an inheritance, and said he was lying.

But jurors at Isleworth Crown Court dismissed her claims and convicted her of both counts following a three-week trial.

Andrea's brother Desmond turned to face his sister's killer in the dock as he read a powerful victim personal statement setting out his family's lives 'changed forever when Janice entered our lives'.

He said: 'She brought abuse to our household that brought extreme fear.

'I was broken and I have never been the same since.

'The last memory I have of my sister's life are my sister's piercing screams and lying about her death.'

Looking Nix straight in the eye as she appeared to shake in the dock, Mr Bernard said calmly: 'Your actions robbed my sister of her life and stole from me the opportunity to grow up with her.

'You took away her future and changed mine forever.

'You fooled my family because they couldn't imagine the unimaginable - you manipulated them so you could not be found out.

'The time has now come for you to acknowledge what you have done to Andrea and myself.'

During the trial Mr Bernard, now 56, described how his stepmother was 'furious' with Andrea when the pair got home from school on Tuesday June 6 1978.

He said he was in his bedroom opposite the bathroom when he heard the screams.

Weeping, he told the court during the trial: 'I could hear her shouting and slapping, and Andrea, of course, screaming and crying.

'Next thing I remember is the bath was running… I could hear footsteps back and forth.

'I could hear shouting from the bathroom. I could hear Janice shouting: "Get in the bath.'

'And I could hear Andrea saying: "The bath is too hot, mummy."

'Then I heard screaming and splashing.'

He said this lasted a 'couple of minutes', after which he said: 'Then I heard the screaming stopping. I could hear Janice telling Andrea to wake up.

'She was holding Andrea in a towel, and Andrea was limp. She was by the bathtub, she was cradling her.

'Her eyes were closed, sort of fluttering.'

He said Nix, then known as Thomas, seemed 'panicked', and added: 'She asked me to say it was an accident, to say that we were in the garden when it happened, and that she would never beat me again.

'I lied, I told everyone that story.'

Mr Bernard said Nix began abusing the children from 'day one' after she started living with them and their father, Desmond Bernard senior, in around 1975.

The brother said Nix hit him with a pot, beat him with a belt, stubbed a cigarette out on him, bit him, and forced him to eat cat food. These were all 'punishments', he said.

Mr Bernard said he and his sister were forced into a freezing cold bath just days before the fatal incident took place.

He told jurors: 'I don't know what we did.

'I don't know what we had done but we were shivering in that bath and she knew it was cold, because we told her it was cold.'

Andrea died in a specialist burns unit in hospital five weeks after being scalded, in agonising pain. 

The court heard Andrea suffered severe burns to 50% of her body following the incident.

Experts believe Andrea was forced or ordered into water exceeding 50C, potentially around 60C, which would have caused unspeakable damage to her young skin.

Nix initially told police she was in the garden at the time, and that Andrea later came downstairs fully dressed and complaining of having 'itchy legs' after being sent off to have a bath unsupervised. 

But she changed her story in 2022 following Mr Bernard's disclosure, claiming she ran into the house when she heard Andrea scream. In both accounts, she denied being in the bathroom at the time.

Nix, who was working full-time as a clerk in the city, could not explain to jurors why she was at home that afternoon.

Nor could she articulate why her initial lie would have protected her from allegations of neglect, given the second version of events still meant the girl was on her own.

During cross-examination by prosecutor Jocelyn Ledward KC, she said Andrea was sent for a bath at 4pm because she was dirty from school.

This was despite maintaining the little girl and her brother, eight, would be playing in the garden afterwards.

She also said she could not remember crucial details about the incident, regularly changing her mind about whether Andrea was clothed or not.

Mr Bernard kept what really happened to Andrea to himself for 44 years until he began receiving counselling and therapy in 2022 after becoming enraged with Nix's memoirs, Breaking Out.

In it, she recalled how she had risen through the ranks of south London's criminal underworld in the 1980s to establish herself as 'Mama J', a glamorous cocaine dealer responsible for flooding the market with premium class A drugs.

She wore designer clothes, had the latest technology, and even drove a Jeep inscribed with her sobriquet 'Nasty Girl'.

Nix was a mother to biological daughter Nadia by the time she was handed a nine-year jail term in 1992 for drugs offences.

In her memoirs, she described how she coached the primary schoolgirl to lie about her - Nix's - whereabouts if she was ever to be questioned by police. She denied ever doing the same to Desmond following Andrea's scalding.

She was handed an eight-year jail term in 2002 over another drugs deal, and said this period of incarceration prompted her to change her life, eventually getting a job with the Probation Service in London.

Nix referenced Andrea just twice in her biography, published by an imprint of Harper Collins, but did not mention the bath incident at all.

The publication of the 330-page tome - and her attempt to claim she had repented for her previous wrongs infuriated Mr Bernard.

He said: 'I went to counselling and therapy so I could deal with this, because I couldn't carry on.

'This was part of my process to tell my parents what happened, and to tell my family what happened, and to just be truthful about it.'

Met Detective Constable Fran Homer, who led the investigation, said the case would never have been reopened without the brother's new evidence, which 'rang alarm bells' with detectives.

She admitted police 'didn't dig deeply' into what happened initially, but that modern policing means officers are trained to 'think the unthinkable'.

She told the Mail: 'It's quite apparent from the description of the injuries versus the account that was given (at the time) that it just doesn't add up.

'You do feel that when you look back... you think: surely somebody thought this wasn't right? 

'They should have asked more questions and done more, and so I think it did very much made the team want to be able to get justice, because for us it was really quite apparent that there needed to be some more questions asked'

She said Nix showed 'no remorse' during her witness testimony, and accused her of repeatedly 'clutching at straws, desperate to throw any kind of mud that would stick'.

She said: 'I think he (Desmond) has found it very difficult, knowing that he has stood and told the truth, that she has stood there and lied and tried to discredit him and muddy waters.'

The officer added: 'For justice to be served so long after, it must feel just very, very good and reassuring in the sense that finally you know she will be serving a custodial sentence for what she has done.' 

Defending, Colin Aylott KC said Nix had 'devoted a substantial part of her time to work of genuine and measurable benefit to others' since completing her most recent prison sentence for drugs offences in 2005. 

He said: 'What this shows, we submit, is the work she has done has not been temporary or short-lived, nor has it been a self-serving exercise. 

'She could never have known there was any prospect of her facing criminal proceedings arising out of Andera’s death.

'There can be no doubt whatsoever that many young vulmnerable women have benefitted from her assistance.'

But he added: 'We do not suggest such work can cancel out the offences for which she has been convicted.'

The judge handed her a 12-year sentence for manslaughter, and a 15-month sentence for child cruelty to run simultaneously. 

She will serve two-thirds of the sentences in prison before being released into the community with strict conditions.