During the first half of the season, Bobby is referred to as being 13 years old, but beginning in episode 1x11 they began referring to him as being 12 years old, which he remains for the rest of the season.
When Jack is shaving in "Chess Lessons", at one point you can still see a bit of shaving cream on the side of his face, and though he does not wipe off his face, the shaving cream is gone in the next shot
Adult Marcus Ride: I'll never forget the day Bobby told Grace that he was a Republican. It was like coming out. Coming out of the closet... as an ax-murderer. There was nothing Grace loathed more than a Republican. I remember she just kept saying that it was so wrong. At the time I thought she meant the party itself was wrong, but now looking back I think what she meant was, it was wrong for him.
Tom Wexler Graham: I hate to break it to you but if apathy defines my generation, yours is defined by disappointing us to where we don't even see the point anymore. The best minds of your generation gave up a long time ago. You know what they do now? Vote for Bush.
Future Courtney McCallister: Grace used to say Jack and Bobby were like two sides of a coin. Without Bobby, Jack might never have learned compassion. Without Jack, Bobby might never have gained strength.