Frasier: Roz! I miss those people. I was trying to find myself. Just as Martin is warming to the idea the door bursts open to reveal Niles, breathless and panting like he's just run a mile. Martin: Her evening? Roz: [holding up a parcel] Happy Birthday! Thanks for a great party! The Doctor is out. They're in Wisconsin at my Uncle's dairy farm having a family reunion.
Plan: A: Roz - unhappy; Q: Who is missing a family reunion? A: Martin; Q: Whose birthday party is Frasier throwing? Summary: Frasier tries to cheer up Roz - unhappy because she is missing a family reunion - by inviting her to the birthday party he is throwing for Martin.