The little kid in The Sicilian movie was just a dedicated follower to Giuliano. I think if I remember correctly he was in released in the Jailbreak of Monreale. A very confusing plot and for no reason he was added (not the jailbreak, the kid). The film had too many problems.

I think the main problem with the film is that it tried to mix the film and the real life things what Giuliano did but still it was innaccurate and didn't have the entertainment of the novel. So it was a huge failure. The book is quite innacurrate but at least it is a very entertaining read. To me one of the greatest books written.