Charlie Gard: US treatment is a 'chance worth taking'
The parents of Charlie Gard say taking their sick son to America for treatment is "a chance worth taking".
They joined supporters to deliver a petition to Great Ormond Street Hospital calling on doctors to allow him to travel to the US for experimental treatment.
The petition has been signed by more than 350,000 people, while the case is due to return to the High Court on Monday.