 The books are set prior to the formation of the Federation of Sentient Planets; in this series, the ruling body is the 'Amalgamated Planets'.The Petaybee universe comprises two trilogies ("Powers" and "The Twins of Petaybee") by McCaffrey and Elizabeth Ann Scarborough.This series introduces a new universe with space faring Barque Cats and their special telepathically linked humans.