Rat out the baby showerers to her boss, keeping her word to her boss but making enemies of her colleagues.
Say nothing; what's her boss so afraid of? Get over it, boss, and eat the cake!
Say nothing, but on the day of the baby shower, call in an anonymous bomb threat so your office is evacuated and the party is averted.
Call in sick until it's all over.
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Created at Crowdsignal.com