When's the happy event?

A) We're thinking of holding a party to celebrate the happy  event. Can you come?

B) We were really proud of our daughter's achievement and decided it called for a  celebration .

C) If you're intending to push  the boat out why not consider renting a hotel for the guests?

 
I didn't know you were pregnant! When's the happy event?

Paula has passed her exams with straight 'A's, which calls for a celebration.

The family have decided to push the boat out and no expense is being spared on the wedding.