Mother weeps as killings described
A depressed mother wept in the dock as a court heard how she smothered her disabled twin sons with a nappy before killing their sister and trying to kill herself.
Tania Clarence, 43, has admitted the manslaughter by diminished responsibility of Olivia, four, and three-year-olds Ben and Max at the family home in New Malden, south west London, over the Easter holidays.
The children were found dead - tucked into their beds with toys arranged around their heads posed as if on a "bier" lying in state.
After just 20 minutes of listening to the "grotesque" details at the Old Bailey, Clarence became too upset and was excused by Mr Justice Sweeney.
Her husband, investment banker Gary, and other family members stayed behind in court despite appearing distressed.
Prosecutor Zoe Johnson QC said all three of the children had suffered from the muscle-weakening condition SMA type 2, and had the Clarences known before the twins were born, they would have agreed to abort the pregnancy.
Days before the killings, Clarence's husband had taken their eight-year-old daughter, who is not disabled, on a holiday to South Africa leaving the defendant alone with her other children, having given a nanny a day off and decided to end their lives in the early hours of April 22.
Ms Johnson said: "She smothered the boys first whilst they were sleeping using a nappy so they would not smell her.
"She found it much harder to kill Olivia, and wrote a letter to her husband in the time between killing the boys and killing Olivia."
The deaths were discovered that night after a nanny, called Jade, was phoned by Clarence's mother who had tried to contact her during the day but without success.
Accompanied by her friend Daniel Magagnin and a pastor, they let themselves into the house and found Clarence in her bedroom.
Ms Johnson said: "Daniel asked Mrs Clarence if she wanted him to pray for her, she told him to go and she was a private person. Mrs Clarence started to say 'it's too late, it's too late, there's nothing you can do to help them.'
"Jade gave Mrs Clarence a hug. Mrs Clarence lay down and pulled the duvet over her. Daniel noticed blood on her wrist and called 999.
"He opened the twins' door and discovered the dead bodies of the twins. It was such a grotesque sight Mr Magagnin could not bring himself to look for Olivia as he was instructed to do by the emergency operator."
Meanwhile, the court heard Clarence handed her nanny a letter, which read: "I'm so sorry I had to do this but I could not carry on. I also could not leave the children with Gary. It would have been too much for him.
"You have been such an amazing person in our lives over the last few years. Without you I most likely would have done this a lot sooner."
When police arrived at the house in Thetford Road, a female police officer found the twins, Ms Johnson said: "Each boy lay on his bed, on his back, with their eyes open and their mouths open.
"Little cars and toys had been placed by their heads. The covers were neatly tucked in and their arms were on top of the covers at their sides.
"Mrs Clarence had clearly placed the boys into some sort of pose, as if they were on a bier."
A male officer found Olivia also in her bed with the covers tucked up to her chin and toys placed around her.
Clarence repeatedly told the officers "I'm sorry, I'm sorry. I killed them".
Ms Johnson went on to outline a long history of the children's medical treatment in and out of hospital and Clarence's attitude that their quality of life was more important than its length.
Clarence repeatedly clashed with medical professionals over the care of their children, opting for palliative care over more invasive treatment, saying on one occasion: "Gary and I do love our children just not in the way you want us to."
In May 2011 a doctor noted that Clarence was "seriously over-stretched/under intolerable strain" from all the medical appointments.
The following year, the family were allocated a social worker with expertise in looking after children under five, but she was replaced by a social worker who had been in the job just six months - an "ill-conceived decision" in hindsight, Ms Johnson said.
In April 2014, Mr Clarence finally agreed to a gastric button for Olivia, but at the same time, Kingston social services called a meeting to discuss the possibility of instituting child protection measures.
Ms Johnson asserted: "Although Mrs Clarence and her husband believed that the only appropriate care for their children was palliative care, the children had not reached the stage when palliative care was required.
"The circumstances of the killings, the planning and premeditation, the intention to kill three children, the fact that Mrs Clarence had failed to address her own depression, her controlling behaviour and her underlying belief, means that her culpability is not extinguished by reason of her diminished responsibility and that her responsibility remains considerable."
Defending, Jim Sturman QC said Clarence had "adored" her children but the problems of caring for them were "almost unimaginable" considering they were unable to feed themselves, walk or hold themselves up.
He said it was not right to say Clarence would have preferred "nature to take its course" when the parents just wanted their children to be happy.
He criticised the actions of the "inexperienced social worker" who had replaced the one who had resigned "in disgust" after being moved off their case because she was an "advocate for the family".
The lawyer added that it was "striking" that Mr Clarence had given his unconditional support to his wife throughout.
Mr Justice Sweeney reserved sentencing until Tuesday on what he described as an "extremely difficult case".