The family of Archie Battersbee - the 12-year-old at the centre of a High Court dispute over life-support treatment - could mount an appeal within days to overturn a judge's ruling that his care should end.
They disagree with doctors at the Royal London Hospital in Whitechapel, east London, who think the youngster is “brain-stem dead” and that he should be disconnected from a ventilator.
Archie's parents, Hollie Dance and Paul Battersbee, from Southend, Essex, say the youngster’s heart is still beating and want treatment to continue.
Mrs Justice Arbuthnot, based in the Family Division of the High Court in London, ruled on Monday that Archie, who suffered brain damage in an incident at home in April, was dead and doctors could lawfully stop treating him.
Relatives said they wanted Court of Appeal judges to consider the case.
A spokesman for campaign organisation the Christian Legal Centre, which is supporting Archie’s family, said relatives will ask Mrs Justice Arbuthnot to give them the go-ahead to mount an appeal on Monday.
Relatives must first establish that they have an arguable case and gain permission to appeal, before an appeal hearing is staged.
Lawyers representing the Royal London Hospital’s governing trust, Barts Health NHS Trust, had asked Mrs Justice Arbuthnot to decide what moves were in Archie’s best interests.
She considered evidence at a trial earlier this month.
The judge heard that Archie suffered brain damage in an incident at home in early April.
Ms Dance said she found him unconscious with a ligature over his head on April 7 and thinks he might have been taking part in an online challenge. The youngster has not regained consciousness.
A vigil was held for him on Monday night outside the hospital where he is being treated, hours after the judge's ruling was announced.
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