For other characters named Doug, see: Doug (Disambiguation)
As Stewie plays with a toy lawnmower in "Movin’ In (Principal Shepherd’s Song)", Doug teases him about mowing the lawn, and Stewie retorts that he would have gotten to it sooner if Doug hadn't borrowed his lawnmower. Doug uses this opening to ask to borrow a shovel to dig to China, and later sends Stewie pictures of his success in indeed reaching China.
Their association begins to take a less-friendly tone when Doug attends Susie Swanson's christening party in "La Famiglia Guy", where he rubs his connections in Stewie's face, including getting to sit at in a table for first graders. When Stewie attacks his parents, Gene and Cheryl's, marriage trouble, the other kids come to Doug's defense, leaving Stewie with egg on his face.
When Brian feels that Stewie has been less than helpful in trying to get him back into shape in "Meg Goes to College", he enlists Doug, who again celebrates one-upping the former. Seeing Stewie's hurt expression, Brian decides to go without exercising at all and aids Doug in getting down the stairs. Aware that Stewie can manage the stairs on his own, Doug is furious, but falls asleep in the middle of his revenge threat.
Due to her failing vision, Lois accidentally hits Doug with the car while dropping Stewie off at preschool in "LASIK Instinct". When Doug's own parents are too busy to attend to him, the family volunteers to build him a treehouse in order to stave off a lawsuit. They soon find themselves roped into other activities. But when the side activities keep piling up, they call his bluff on notifying his father, and Stewie attempts to call him himself. However, they discover that Doug is holding his father's phone and has been pretending to keep adding to their activities in order to spend more time with them. When Doug's own father arrives and gives him the brush-off just so he can spend time with his mistress, Chris and Brian both offer to poop in his shoes in retaliation, while Doug and Stewie agree to keep their hostilities toward each other away from their private lives.
The boys' dynamic would be further explored in "80's Guy"; when they compete to retrieve a frisbee off the top of the jungle gym, they get stranded at the top and have a heart-to-heart about their rivalry. For Doug's part, he admits that he acts like a jerk and constantly shows Stewie up because he's intimidated by his brilliance, and is envious of his minimal hair. Although this turns out to be a ruse to claim the frisbee and hog the glory, Doug reconsiders after Stewie saves his life, and the two share the credit, now seeing each other in a slightly different light.
- FG1717 "Island Adventure"
- FG1820 "Movin’ In (Principal Shepherd’s Song)"
- FG1905 "La Famiglia Guy"
- FG1914 "The Marrying Kind"
- FG1917 "Young Parent Trap"
- FG1918 "Meg Goes to College"
- FG2001 "LASIK Instinct"
- FG2004 "80's Guy"
- FG2005 "Brief Encounter"
- FG2006 "Cootie & the Blowhard"
- FG2008 "The Birthday Bootlegger"
- FG2018 "Girlfriend, Eh?" (mentioned)