A doctor has said that a baby in a "right-to-life" legal row has the potential to communicate and even operate a wheelchair in years to come.
The paediatric neurologist, Professor Fenella Kirkham, told the High Court that Baby RB had the normal intelligence of a one-year-old.
She said he was likely to develop language recognition skills and he may be better off at home.
The boy's father is fighting an attempt by the hospital to end life support.
I would have thought that, with a good home ventilator package, he would be better off at home
Professor Fenella Kirkham, paediatric neurologist
The hospital is supported by the mother, who agrees with the lawyers who say her son will lead a "miserable, sad and pitiful existence", even if surgery allows him to be returned home.
Instead, they say they are seeking permission to withdraw fundamental life support "to allow him a peaceful, calm and dignified death".
One-year-old Baby RB is believed to suffer from a rare, genetic condition called congenital myasthenic syndrome (CMS) which makes it impossible for him to breathe independently.
But Professor Kirkham said the CMS diagnosis was not certain.
She said genetic research was still being carried out to discover the cause of his condition, since he had not responded to the drugs normally used to treat CMS.
She said it was possible that a carefully balanced drug regime, using frequent but small doses, would improve his quality of life.
Professor Kirkham said video recording showing the boy responding to his parents' voices and banging a drum or kicking a ball, were indications that his movements were "purposeful".
Baby RB's father believes he might be taken off his ventilator and returned home if surgeons carried out a tracheotomy, which creates an opening in the neck to deliver air to the lungs.
His doctor has agreed to carry out a tracheotomy assessment on Saturday and report back to the court next week.
Professor Kirkham said: "One of the main reasons for discharging patients is that there are more nasty bugs in hospital than at home.
"I would have thought that, with a good home ventilator package, he would be better off at home."
On Tuesday, another clinician - Dr F, a paediatric intensive care consultant, agreed with the boy's hospital and his mother that his quality of life was so low that it would not be in his best interests to try to save him.
He told Mr Justice McFarlane that baby RB was living "on a knife edge" and could suffer even greater distress if a tracheotomy was performed and some sort of blockage or infection developed.
On Wednesday, a clinician - Dr M, a paediatric intensive care consultant, admitted that baby RB may be able to interact - but said his future remained tragic.
For legal reasons, none of the parties in the court case can be identified.
Both parents, who are in their 20s and are said to be "amicably separated", have been present at the hearings.
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