Transcript for NY doctor arrives in London to begin evaluation of terminally ill 'Baby Charlie'

Overseas tonight, and new developments in the case of baby Charlie at the center of a tug of war. An American doctor beginning his evaluation of 11-month-old Carley gar. ABC's James Longman from London tonight. Reporter: Today, Charlie's family got the chance they've been fighting for. A team of doctors spent the day at his side, to determine if he might benefit from experimental treatment in the United States. His genetic disease has left him unable to move, see, or even breathe on his own. Doctors say he should be allowed to die. A U.S. Family whose six-year-old son suffers from the same condition tell ABC why they, too, opposed the medical opinion. I had a strong intuition that something was wrong. I was right. Reporter: These are parents united in a struggle for their children. This is the man Charlie's parents are pinning their hopes on -- Dr. Michio Hirano, a neurological specialist from Columbia university. He believes there's a 10% chance the 11-month-old's muscle strength could improve. This is perhaps a battle of parental instinct versus medical reason, but it's a battle the courts will have to settle. And Charlie's wait may soon be coming to an end. The team of doctors will send their report to the high court this week, for the judge to make his long awaited ruling. David? James Longman in London. Thank you. We'll have much more on baby Charlie, and the American family pioneering treatment. That's later tonight

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