I think that Lena Olin's a great choice to play Sidney's mom. The only concern that I have is with the Rimbaldi sketch that we saw - it looked very much like Sidney, but the prophecy no longer applies to her as she took the trip and saw the mountain, so it was generally assumed that the sketch would be of her mother instead...and Lena Olin doesn't look like Jennifer Garner. As long as it gets explained in a way that makes sense somewhere along the line, I'll be happy. Alias is a great show!