Joey was two and Scotty 22 months when we made this movie.  We had recently refurbished all of the dogs' obstacle course equipment and wanted a video to remember how colorful everything looked (as it fades over time).  We show the dogs going over/through the various obstacles . . . then we used chroma-key techniques to place the dogs in "scene" locations performing actions that fit the environment - similiar to how commercial movies do it.