CALLING ALL CAHILLS Announcing a 39 Clues Superspecial adventure -- the gang is back, and called to investigate one of their own: Sinead Starling.A TRAITOR RETURNSThe Cahills are the most powerful family history has ever known. For the past five centuries, they have secretly served as guardians of the world. The Cahills command presidents, take down corrupt governments... and are currently led by a fourteen-year-old boy with a superhero complex.Dan...