FRESNO, Calif. (KFSN) -- As part of a plea deal, Harper admits to arson fire that caused Pete Dern to fall through the roof, and she will serve nine years in state prison.Harper will be formally sentenced on May 4th.Deputy District Attorney Dennis Verzosa stated that "after a review of the entire investigation, and after careful consultation with Firefighter Peter Dern and his family, the Fresno Fire Department, and the Investigating Officers, we feel that this is an appropriate and fair resolution to this case. With this plea agreement, Firefighter Dern can now attempt to put this horrific incident behind him and focus completely on his recovery."Fire Capitan Pete Dern fell through the roof of a burning garage on March 29, 2015. He spent nearly six months in the hospital recovering from life threatening burns.Stay with Action News and ABC30.com for more on this story.