A woman fighting to stop doctors ending life-support treatment for her 11-month-old son says the youngster responds to her touch, a judge has been told.
Specialists at King's College Hospital in London say giving further intensive care treatment to Isaiah Haastrup is "futile, burdensome and not in his best interests".
Isaiah's mother Takesha Thomas and father Lanre Haastrup, who are both 36 and from London, want treatment to continue.
Mr Justice MacDonald is overseeing a trial in the Family Division of the High Court in London.
A specialist treating Isaiah said the little boy had suffered "catastrophic" brain damage due to being deprived of oxygen at birth and was profoundly disabled.
He told the judge that Isaiah was in a "low level of consciousness", did not respond to stimulation and could not move independently.
But he said Miss Thomas thought that Isaiah responded to her care.
"She feels that Isaiah responds to her face and to her touch," he said.
"We sought to reproduce those responses for ourselves."
The specialist said he was not arguing that Ms Thomas's opinion was less valuable.
"What I bring to this decision is experience of caring for children with profound brain injury," he said.
"I would not argue that my opinion is more valuable than the mother's.
"I bring to it a different level of training and experience."
The specialist said he had seen "no significant change" in Isaiah's condition and thought that he would not improve.
He said the boy could not breathe independently and that evidence suggested that he was experiencing pain.
Barrister Fiona Paterson, who is representing King's College Hospital NHS Foundation Trust at hearings, has told Mr Justice MacDonald that Isaiah was born at King's College Hospital on February 18 2017.
She said he was "ventilator-dependent" and being cared for in a paediatric intensive care unit.
Doctors did not think there were any "further investigations or forms of treatment" which would benefit him.
She said nobody could understand the pain and suffering Isaiah's parents had endured.
But she said "overwhelming medical evidence" showed that stopping treatment was in Isaiah's best interests.
Mr Justice MacDonald is hearing evidence at a private trial.
He says the case can be reported but has ruled that medics involved in Isaiah's care cannot be identified.
The hearing continues.