Robert Pattinson paid a secret visit to the Children's Hospital Los Angeles last week.

The 27-year-old hunk thrilled patients, including two huge 'Twilight Saga' fans with cystic fibrosis, when he spent the day with them.

Lyndsay Hutchinson, the hospital's public information officer told People: ''We couldn't help laughing and smiling when one of the patients was so starstruck that she couldn't speak. You could tell it meant the world to her - she was tearing up and smiling ear to ear. The other little girl teased him relentlessly and begged him to do an American accent. They were instant friends.''

Robert also spent time in the hospital's Teen Lounge where he joined patients who were decorating picture frames.

Child Life specialist Ana Vega said: ''Robert was so nervous about meeting the kids - he didn't want to let them down - which is a testament to how humble he is. He was incredibly gracious and kind.''

Robert recently admitted he was unprepared for the way his life would change after he shot to fame by starring as vampire Edward Cullen in the 'Twilight Saga'.

He said: ''I lived in a small apartment when the premiere arrived and didn't even know if the sequels would be made. Then came the weekend of the premiere and it was, 'Oops, now we must do the sequels.' ''