Baby P's "stepfather" is facing a life sentence today after being convicted of raping a two-year-old girl who should have been protected by social workers.
The girl, like the 17-month-old toddler who can now be called Peter, was on the Haringey Council child protection register.
The anal rape allegation came to light after the 32-year-old man and Peter's 27-year-old mother were arrested for his death.
The woman was found not guilty today by the jury at the Old Bailey of cruelty to the girl.
The couple cannot be identified for legal reasons and were tried under false names amid fears that an internet hate campaign would try to influence jurors.
The jury of eight men and four women had no idea of the defendants' true identities.
They were told by Judge Stephen Kramer after they delivered their verdicts following three days of deliberations.
He said the couple were tried under false names to ensure they got a fair trial.
There was no apparent reaction from the jurors after he revealed that they had been trying a case connected to Peter.
The man and woman were remanded in custody for sentencing on 21 and 22 May. The man will be sentenced for rape, and for causing or allowing Peter's death in August 2007 along with the mother and lodger Jason Owen.
The convictions mean the judge will be able to pass a life sentence on Baby P's stepfather if he considers him to be a danger to the public.
Peter's mother and her lover, whom the boy knew as "dad", lived in north London.
They were cleared last November, along with lodger Jason Owen, 36, of Peter's murder.
Baby P's mother pleaded guilty to causing or allowing the death and the men were found guilty by a jury. The maximum sentence for the offence is 14 years.
Judge Kramer warned the couple today: "The likelihood is of very substantial sentences in both cases."
There was a storm of protest when details of Peter's death emerged and criticism of police, social workers and medical staff.
Peter was found dead in his blood-spattered cot with a broken back and fractured ribs.
He had 50 injuries - despite having had 60 contacts with health and social workers over the last eight months of his life.
In the latest trial, the girl victim became the youngest child to give evidence at the Old Bailey.
The court was shown her video interview with police when she was three, in which she said the man had hurt her.
The 30-minute tape was shown to the jury as her evidence, and then she faced cross-examination from defence lawyers.
In the tape, the bubbly youngster giggled as she wriggled on and off a blue armchair in a special police interview suite.
She answered questions put to her by a specially-trained female police officer in a lively, infantile voice.
Then the girl appeared on a videolink screen after watching the interview on her own screen in a room at the court.
She played with two teddy bears and a toy hedgehog as she said she knew what lies were, and the difference between fibs and the truth.
Although older and changed in her appearance, the girl retained the same sunny smile.
But it soon fell away when she was questioned. She went silent and refused to answer questions about why she initially told police the man had not touched her.
Asked if she had been fibbing, the girl appeared traumatised and at one point rubbed her eyes.
After an overnight break, she was back to her old self and told Sally O'Neill QC, prosecuting, that what she said in the taped interview was the truth.
Defence barristers argued that the child's evidence was not reliable and the allegation could have been suggested to her by another child.
Medical evidence was inconclusive but a test showed a finding which "could be supportive" of the allegation.
The rape claim was made to an adult a few months after it happened, the court heard.
The girl was seen by a police officer the following month but shook her head when asked if the man molested her.
The allegation re-emerged last year when the girl was seen by a psychiatrist. She repeated it to another doctor.
Miss O'Neill told the jury that the girl made "spontaneous" statements not influenced by leading questions.
She said: "It is unusual for a child of this age to give evidence in a criminal trial, but her age is only one feature, albeit an important one, in this case."
She said the girl demonstrated the attack on her to the psychiatrist by using a doll and a toy bear.
Miss O'Neill said the girl demonstrated the man's position to police, adding it was "like penguins do".
Neither defendant gave evidence but they denied the charges.
Baby Peter suffered months of ill-treatment, culminating in his death after a punch in the mouth knocked one of his teeth down his throat. It brought an outpouring of public emotion and criticism of care workers.
More than a million people signed a petition, organised by the Sun newspaper and delivered to Downing Street, demanding that social workers should be sacked.
A shrine grew up near the spot in a north London cemetery where Peter's ashes were scattered.
A hate campaign grew and there were demands that the trio be given life sentences.
The 15-year-old lover of Owen told a newspaper that the mother's boyfriend was responsible for Peter's injuries and said she had seen him squeezing him until he could not breathe.
Peter's mother used cunning to hoodwink social workers, health officials and police after hiding the presence of the two men and girl at her north London home.
The house was not searched even though Peter's natural father suspected the man was living there.
The mother, who had contact with social workers for most of his life, managed to hide Peter's broken back from a doctor at a child development clinic after persuading her to cut an examination short two days before his death.
Dr Sabah Al-Zayyat is still being investigated by the General Medical Council, which has also suspended her registration.
Family doctor Jerome Ikwueke is also under investigation.
Haringey Council faced huge criticism after it emerged that Peter was on its child protection register and had been returned to his mother even though she had been arrested twice on suspicion of assaulting him.
After the Baby P trial, Prime Minister Gordon Brown even got involved, pledging to do "everything in my power" to prevent a repeat of the tragedy.
Children's Secretary Ed Balls ordered an urgent review of Haringey's children's welfare services.
Inspectors delivered a damning report to Mr Balls, who describes their findings as "devastating".
Mr Balls removed Sharon Shoesmith, who had refused to apologise over the death, as the local authority's director of children's services.
She was later sacked by a panel of councillors and told she will not receive any compensation.
During the trial, it emerged that social workers had tried to keep the family together, not suspecting that the mother was harbouring a sadistic partner in the house.
Maria Ward visited the house four days before the death and missed bruises on Peter's face because they had been covered up with chocolate.
Miss Ward said she had been content to leave the boy with his mother because she appeared to be co-operative and properly supported.
But she became one of four key social workers sacked by Haringey on 30 April. Miss Ward, team manager Gillie Christou and head of safeguarding services Clive Preece were dismissed for gross misconduct.
Deputy director of children and families Cecilia Hitchen was dismissed for loss of trust and confidence following a damning Ofsted report.
But police said they had no plans to launch a criminal investigation into the council's conduct.
Inquiries had found incompetence, not criminal failings.