A young French boy who was thrown off the 10th floor viewing platform of London's Tate Modern art gallery has uttered his first syllables, his family said.The six-year-old suffered a broken spine, legs and arm in the attack, which happened in front of horrified visitors to the riverside contemporary art gallery on August 4.Jonty Bravery, 18, pleaded guilty to attempted murder at a hearing in London's Central Criminal Court on December 6 and is in custody awaiting sentencing.In a post published on Wednesday on a GoFundMe page helping to pay for their son's recovery, the family said the boy has also regained some movement in his limbs."Our little knight begins to speak!" the family wrote."He pronounces one syllable after another, not all of them, and most of the time we have to guess what he means but it's better and better. It's a wonderful progress!"But the family stressed he remained in great pain and that progress was slow."As he begins to move, sensations come back and he feels more pain, above all during the night, which is very exhausting for everybody, but he is very courageous and we stay strong for him."The boy fell from the viewing platform onto a fifth-floor roof below. Prosecutors at Bravery's last court hearing said it was "extraordinary" that he survived at all.Bravery's lawyer Philippa McAtasney told the court that her client had autistic spectrum disorder, obsessive compulsive disorder and was likely to have a personality disorder.The court was told he claimed to have heard voices tell him he had to hurt or kill people, and that he said to police he wanted to "prove" he had a mental health problem.