Continuity mistake: In series 4 episode 13 Jungle Love: When the family are escaping the tribespeople, Chris is wearing the tribal clothing. When they jump in the plane there is a brief far-off shot of Chris wearing his usual cap and t-shirt. In a close up shot moments later, he is wearing the tribal gear again.
Other mistake: In the kitchen when Peter is playing with the paddle ball and then Brian confesses to giving Chris the idea about joining the Peace Corp, there is a picture frame on the wall behind Peter. In this is various pictures of the family including Brian. In this, Brian is as a yellow dog despite being white in the series, and even in the scene depicted.