The girl's divorced parents have been in a dispute over whether their daughter's remains could be flown to a specialist facility in the US and preserved.
Suffering from a rare form of cancer, the teen asked a High Court judge to rule that only her mother could make decisions about the disposal of her body, as she backed the girl's wishes to be preserved.
Her father disagreed however, and was concerned about the consequences of being frozen.
'She may be left in a desperate situation'
He told High Court judge Mr Justice Peter Jackson: “Even if the treatment is successful and she is brought back to life in, let's say 200 years, she may not find any relative and she might not remember things.
“She may be left in a desperate situation – given that she is still only 14-years-old – and will be in the United States of America.”
The schoolgirl died on October 17.
Mr Justice Jackson made the ruling the teen wanted in October, and lawyers have revealed she has now been taken to the US and frozen.
The procedure involves the storing of living cells at very low temperatures and can be used to preserve blood cells, sperm and embryos.
Unclear if the process will win
But the process has not been successful on bigger objects such as kidneys, so it is unclear that a body could survive being cryogenically frozen.
He also ruled that no details from the case should be reported while the teen was alive, as the coverage might distress her, and he ruled that no-one involved should be identified.
The teen was too ill to attend the court hearing, but had written to the judge to explain she wanted a chance to “live longer”.
Mr Justice Jackson had also visited the girl in hospital, and was moved by the “valiant way” she faced her situation.
The judge said: “No other parent has ever been put in his position.
“It is no surprise that his application is the only one of its kind to have come before the courts in this country – and probably anywhere else.
“It is an example of the new questions that science poses to the law – perhaps most of all to family law."
Teen was determined
The judge said the girl had carried out research into the procedure and was determined despite the efforts of some to dissuade her.
He added that the relationship between the girl's parents was “very bad”, and the teen had lived with her mother for most of her life.
She had refused to have contact with her father, had not wanted him to have detail of her illness and had not wanted him to see her body after she passed away.
However, during the hearing the father's position changed.
"I respect the decision she is making"
He said: “I respect the decisions she is making. This is the last and only thing she has asked from me.”
The case was heard at a private hearing in the Family Division of the High Court in London.
Mr Justice Jackson said there was a “tragic combination” of childhood illness and family conflict.
But he agreed with the mother's decision to let her daughter be frozen, saying it would be in her best interests.
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