This is from the Stephen Sondheim Society website...
"Ed Sanders and Jamie Bower, both National Youth Music Theatre alumni, are appearing in Tim Burton's film of Sweeney Todd, playing Tobias and Anthony Hope respectively."
Toby = simple-minded adolescent. Depending on the nature of the National Youth Music Theatre, he could still easily be a fairly young child, or at least a mid-to-late teen who plays young.
I posted pictures of these two kids a few weeks ago in some thread on BWW. Jamie Bower is 19 or 20. Eddie Sanders is about 11. The National Youth Music Theatre has students from seven to 18.
[edit] Cast Johnny Depp ... Sweeney Todd/Benjamin Barker Helena Bonham Carter ... Mrs. Nellie Lovett Alan Rickman... Judge Turpin Timothy Spall ... Beadle Bamford Sacha Baron Cohen ... Signor Adolfo Pirelli Jayne Wisener ... Johanna Laura Michelle Kelly ... Beggar Woman Christopher Lee ... Ballad Ghost Anthony Stewart Head ... Ballad Ghost Peter Bowles ... Ballad Ghost Sam Kenyon ... Ensemble Loren Geeting ... Ensemble Alastair Lindsey Renton ... Ensemble
If you notice, both Christopher Lee and Anthony Stewart Head are mentioned as Ballad Ghosts. Wikipedia has a whole thing about the Sweeney movie and it mentioned that Burton was originally intended to direct Sweeney way back when, but dropped out and Sam Mendes took control, but then of course last year Burton retook the reigns.
"They are playing ghosts of people that are killed during the course of the film (including Fogg and others)."
That thought had crossed my mind, it make sense. Lee is Fogg though right?
I was on IMDB and heard the oddest rumor about Sweeney. It was that the musical numbers were going to be sung like an internal monolgue. That doesn't make any sense, it could work for solo moments, but not as much for something like a duet.