I'm sure they will in some flash backs, but for others he might be too young I think.
I think the Voldemort who killed Lilly and James was much older than the Tom Riddle from SoC.
Dunno, just a guess, and the reps could be right, maybe Joseph won't even be in it.

So what exactly did Sirius fall back into then?

I didn't even get that Bellatrix died either. I thought she was just stuck in a fireplace.

This movie is so confusing, I think I'll download it and watch it again.
Or maybe I should just read the book.

sirius fell into a portal to the "other side" ... the other side being death. but they really don't explain that AT ALL in the movie and just have bellatrix avada kadavra him when that doens't even really happen!!

and bellatrix didn't die in the movie, she escaped through the flu system thing. maybe you are confused because of people talking about the last book?

but yeah, READ THE BOOK!

hm i didn't think about the fact that there will be voldys of all different ages!! they could use makeup ...? hahah