Rigby's Parents (Barbera and Sherm) are minor characters that appear in the episode "The Thanksgiving Special"; Barbera also makes an appearance in "Rigby in the Sky With Burrito" and Sherm makes an appearance in "Lunch Break". They apparently live far enough away from the park to warrant taking a plane to visit their son. This is debatable, since they seem to live close enough to Mordecai and Rigby's high school, West Anderson High School, which is close to the park