I agree, Chuck has grown up alot, he realizes that people in the spy world are not always who they say, so he will be upset, but don't think he will be real angry with Sarah, especially since at the beginning of the episode he thought his mother was bad, and also when she shot him, again he thought she was bad.
I have seen much worse dresses than that one, it was flashy and loud, but again it could have been worse (and I'm a guy, so I liked the way it accented her legs
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No Sarah Lancaster is not pregnant Here is an interview with her and Ryan McPartlin (Awesome) where it she mentions the foam baby belly belt:
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