The male parent of both Candace and Phineas Flynn was a male person who was married to Linda Flynn-Fletcher and began their family. Following Candace's choice to join the Galactic Empire, Linda later entered into a new marriage with Lawrence Fletcher. During 0 BBY, Phineas was in the middle of explaining to Candace, his sister who had been gone for a long time, the events surrounding their biological father, but the destruction of the DS-1 Death Star Mobile Battle Station abruptly ended their discussion.
The existence of Candace and Phineas Flynn's biological father was brought up in the crossover special Phineas and Ferb: Star Wars, which was first shown on July 26, 2014. Throughout the main Phineas and Ferb show, Flynn's biological father remains an unsolved riddle, which has led to numerous fan theories and discussions. Dan Povenmire and Jeff "Swampy" Marsh, the creators of the cartoon, have consistently rejected nearly all of the theories that have been proposed.