The parents of Ashya King have claimed doctors said they would lose their parental rights and that their son would be taken from them if they continued to ask questions about his treatment.
The couple said they were given conflicting information about their five-year-old's care.
When they did their own research and asked questions following surgery to remove a brain tumour at Southampton General Hospital they say they were threatened with losing their child, the Daily Mail reported.
“If you continue with these questions your rights to make decisions will be taken away from you,” one doctor was alleged to have told them.
“We will apply to the family court to have your parental rights removed and then we will give him any treatment we want.”
Brett and Naghmeh King said they pleaded with medical staff for Aysha to undergo proton beam therapy after they were told a course of radiotherapy would adversely affect his quality of life and possibly leave him with long-term side effects.
They told the Daily Mail that the NHS formed its decision for treatment on the basis of survival rates and not quality of life.
Press officials at the hospital did not respond to calls from the Independent for further comment.
The Kings travelled to Europe and were arrested in Spain after they pulled Ashya out of care in a bid to reach the Czech Republic to receive the proton treatment. Now in Prague, the NHS has subsequently agreed to pay for the course of care oversees.
Southampton General Hospital has denied that its doctors ever threatened to seek a court order to remove the Kings’ rights to make decisions about Aysha’s care. It has defended its decision to recommend standard radiotherapy and chemotherapy and said its treatment plan for Ashya complied with NHS best practice guidelines for cancer care.
Naghmeh described her distress at being arrested as she tried get into an ambulance to accompany her son to hospital in Spain. One officer was reportedly overheard saying: “What sort of world do we live in where you take a sick child away from his mother”.
In pictures: Ashya King's case
In pictures: Ashya King's case
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Brett King, back left, and Naghemeh King, right, accompany their son Ashya King (5) center, as he arrives for pre-cancer treatment examinations at the Motol hospital in Prague, Czech Republic
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Ashya King (5) arrives for pre-cancer treatment examinations at the Motol hospital in Prague, Czech Republic
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Brett King, father of five year old Ashya King, talks to members of the press after holding a press conference at his lawyer's office in Seville, Spain
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Brett and Naghemeh King, parents of Ashya King, attend a press conference in Sevilla, Spain. The British parents are heading to see him at a hospital in southern Spain following release their from custody after United Kingdom authorities dropped accusations of child cruelty against them
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British couple Brett (L) and Naghemeh (2L) King leave Soto del Real Prision in Soto del Real, near Madrid, Spain
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Brett King leaving Soto del Real prison near Madrid, Spain after British authorities dropped the case against him and his wife for taking their son Ashya from Southampton General Hospital without the consent of doctors
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Naghemeh King leaves Soto del Real Prision in Soto del Real, near Madrid, Spain
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Ashya King in hospital with his mother
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Journalist work outside the Materno Infantil Hospital where Ashya King is hospitalized in Malaga, Spain
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Ethan Dallas and Sanjay Ganatra, friends of the family, deliver a petition of over 100,000 names calling for his parents' release from a Spanish jail
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Spanish judge Ismael Moreno arrives to the National Courts to take statement to the parents of Britain's five-year-old boy Ashya King, in Madrid, Spain
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Ashya King parents's lawyer, Juan Isidro Fernandez Diaz, arrives at the National court in Madrid
AP Photo/Andres Kudacki
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Spanish policemen stand guard as a police van carrying the parents of Ashya King arrives at the courthouse in Madrid
JAVIER SORIANO/AFP/Getty Images
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Ashya King’s parents after their court appearance
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Ashya King's father explained why he took his son to Spain in a video uploaded to YouTube
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This photo of Ashya King being examined by doctors in hospital was posted on Facebook by his brother, Naveed
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Ashya King and his brother Naveed
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Ashya King on a hospital bed
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A CCTV still issued by Hampshire Police of Ashya King with his father Brett King at around 4pm yesterday
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The exterior of Southampton General Hospital where Ashya King, who has a brain tumour was taken by his parents from the hospital without the blessing of doctors
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Hampshire Constabulary said there are 'serious concerns' for the life of Ashya King as he needs constant medical care. Officers said his parents - Brett, 51, and Naghemeh, 45, - boarded a cross-Channel ferry from Portsmouth to Cherbourg at 4pm yesterday with Ashya's six siblings
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Ashya King, who has a brain tumour and was taken by his parents from hospital without the blessing of doctors
Criticism and public outcry over perceived "heavy handedness" of the police and prosecutors over the case led to a nationwide fund raising effort.
Doctors in Prague say his type of brain tumour has a 70 to 80 per cent survival rate and hope he will make a full recovery.
While pleased with his progress, his parents said their enforced separation had scarred the five-year-old, who now howls in protest if either of them steps away from his bedside.Reuse content