Joshua is the father of Finn, Jake and Jermaine. He and Margaret (his wife) found Finn in the Mountain Kingdom where they adopted him. Joshua first appears in “Memories of Boom Boom Mountain” in which Finn flashes back on when he was a baby when he did a boom boom on a leaf. Finn claims he went a whole day lying on a stinky leaf. Margaret picks up Finn and thinks he’s cute. When Mountain Man asks Finn if he can stop the marauders rough-housing, Finn flashbacks on Joshua and Margaret. Joshua also appears in “Crystals Have Power” in which Jake flashbacks on he and Jermaine together, Jermaine on the ground, probably punched by Jake, and Jake says that he’s sorry, but Joshua says that Jake will hurt everybody. It is revealed later in the episode that Joshua meant everyone who is evil. In “Crystals Have Power” it is confirmed that Joshua is dead.