A mother who admitted suffocating her three disabled children before trying to kill herself will not face trial for murder, a court has heard.
Tania Clarence, 42, had pleaded guilty to the manslaughter of Olivia, four, and twins Ben and Max, three, by diminished responsibility, but denied murder.
At a hearing at the Old Bailey in London, Mr Justice Sweeney accepted her plea which means she will no longer face trial in the new year.
Clarence, who was not in court, will be sentenced on 14 November when she is likely to face a hospital order.
Prosecutor Zoe Johnson QC said: "It is clear on the evidence Mrs Clarence killed her three children because she wanted to end their suffering and at the time she committed the act she could not see any alternative or any other way out of their joint suffering."
Clarence smothered the three children at their home in New Malden, Surrey, in April.
The court heard she was 'depressed and wanted to end their suffering... she could not see any way out'.
The mother was arrested after police were called to her home and discovered the bodies of her three youngest children.
The children, who all suffered spinal muscular atrophy (SMA) and faced a shortened life expectancy, were found dead by the family's devoted nanny and a neighbour.
Clarence's husband Gary, a 43 year-old director at the City investment bank Investec, had been in their native South Africa with the couple's eldest child at the time.
The three children had not been expected to live beyond the age of five. Post-mortem examinations were carried out at Great Ormond Street Hospital and Mr Clarence immediately flew back to London after being told about their deaths.
Clarence was pregnant with her twins when the family discovered that Olivia had a life–limiting genetic condition.
Doctors warned her there was a 50 per cent chance her twins may also have SMA, which causes muscle wasting and leads to breathing difficulties. .
Tests confirmed the diagnosis when the boys were born and the couple had to confront the prospect that three of their children were unlikely to live beyond their fifth birthday.