I'm going to a baby shower later today for my sometimes boss. I'm really happy for her since she's wanted a kid for a long time and she's overjoyed about being pregnant. Anyway, what is appropriate to say to her and her husband? I don't want to say something stupid or offensive but at the same time I don't want the only thing I say to her to be "congratulations!" Polite questions wanted, please.

Also what the hell do guests talk about? Do you just like...talk about whatever? Do you focus on the baby stuff? I've never been to a baby shower so this is all new for me.