Carrie Underwood, Kellie Pickler and Gloriana are featured on a new compilation album, A Very Special Christmas 7, released this week. Underwood contributes "Hark! The Herald Angels Sing," while Pickler offers "Santa Baby" and Gloriana perform "Silent Night." The collection also includes Miley Cyrus, Colbie Caillat, the Carter Twins, Charice, Kristinia DeBarge, Vanessa Hudgens, Sean Kingston, Leighton Meester, Mitchel Musso and Ashley Tisdale. Proceeds will benefit the Special Olympics.