My kids are 5 and 7 and they loved this movie. There is some wonderful slapstick comedy - especially with the pet-snatchers. Sure, to an adult the plot may be unbelievable, but this isn't aimed at adults. The dog is cute, the story is simple, and you feel good at the end. My kids were laughing and bouncing on the couch - a sure sign of a good movie. (Oddly enough, we got this free on DVD in a box of cereal.)
Tell Your Friends