Christmas Medley (What Child is This / Away in a Manger): Trio for Trumpet, Trombone and Piano for Trumpet,Trombone,Piano written by James R. Murray. The format of this sheet music is Score,Set of Parts and it’s published by John A. Dempsey. Christmas Medley (What Child is This / Away in a Manger): Trio for Trumpet, Trombone and Piano is part of the following sheet music categories: Christian,Spiritual,Sacred,World,Christmas.