Visible crew/equipment: When Cody is saying to Mark "You know it's really good to see you're dating," a crew member steps into the shot on the right side of the screen. (00:08:45)
Visible crew/equipment: When Cody is handing Carol the cashier's check, a camera and a crew member's arm are briefly visible on the right side of the screen.
Answer: According to the SBS website, Brendan's disappearance was never really explained. He just kind of faded out. He was hired as the cute "little" one and as he got older he wasn't as cute. When the Lamberts had the little girl, they got their cuteness factor back and didn't need as many kids around.
Carol and Frank continued to tell people they had seven children throughout the remainder of the show's run, but they never referred to Brendan after season 6.