14-year-old Jack impressed the judges at the weekend with his witty one liners, many of which played on his disability.
It's not Jack's first time in the limelight, having won a Pride of Britain award for his charity work last year and previously performed alongside Jason Manford on stage.
Speaking to the Daily Mirror this week, Jimmy said: "You wouldn’t bet against him becoming a star.”
The often controversial comic added: “I met Jack thanks to the Mirror’s Pride of Britain Awards and he’s brilliant. He knows how to write a one-liner and he’s fearless, cheeky and funny.”
Talking to us yesterday, Jack revealed how he turned to comedy as a way to help him with his disability.
He said: "It can be taxing, I do get a few aches and pains. Laughter is the best medicine.”
And Jack admitted he'd be overwhelmed by the reaction from viewers, adding: "The reaction has been largely positive, I've really enjoyed it, it's been a hectic couple of days. It was a bit weird watching myself, it were nice enough."
Watch our chat with Jack below...