Claire: How does it feel to turn 30?
Roberta: It's like any other birthday 
Roberta: You don't become "mature" from one day to the other
Gertrude: I had a big party but nothing really changed
Gertrude: I don't feel significantly older 
Claire: I'm turning 30 next week!
Gertrude: Welcome to the club
Claire's 30th birthday is next week. Roberta and Gertruda are already 30 and don't feel any different than before.