Joe Heffernan is Doug's father and the husband of Janet Heffernan. Also the father of Stephanie Heffernan, Doug's sister, Joe is played by actor Dakin Matthews. Joe, who was introduced to audiences in the episode "Departure Time" (#3.11)" (2001), is characterized as irascible, somewhat gruff, but still loving to his wife and family, and also is somewhat of an obsessed model train enthusiast, as shown in the 2004 episode "Offtrack... Bedding" (#7.6). Doting wife Janet serves usually the voice of reason to counter Joe's rather gruff, opioniated ways. Joe appears in a total of 13 episodes of the series.