Sleepover Sleuths (Nancy Drew and the Clue Crew, Band 1)

Eight-year-old Nancy Drew has her first case to crack! Can you help?
Nancy and her two best friends, George and Bess, are so excited! They have been invited to Deirdre's sleepover party! There will be pizza, cake, and even a pajama fashion show. But the most exciting thing is that the party has a City Girls doll theme. All of the guests are bringing their dolls with them!
But then Deirdre's City Girls doll -- Hollywood Heather -- goes missing. Is her sleepover ruined? Or is there a detective in the room who can make sense of this mystery?