The scene where Lulu tells Shane that she thinks he's cute and Shane's embarrassed response was based on a real-life incident on set. Morgan York (the actress who plays Lulu), upon meeting Vin Diesel, actually said that to him and he awkwardly responded with a "thank you". The director thought it was so funny that he put it in the film.
Originally, Jackie Chan was attached to this film. The ninjas in the movie are from his stunt team. Ironically, Jackie Chan would later appear in The Spy Next Door (2010) which has a similar premise to this film.
Just to get one shot of the baby falling asleep towards the end of the movie, they had a camera on him for four hours.
Boo Berries cereal is not sold in Canada. Adam Shankman's assistant had to drive to Buffalo, New York to get it.