The continuity seems a little confusing/messed up. In the first movie Josh was in Middle School/Played basketball and Andrea was around 2/still a baby in a high chair.
In the second film Josh's mom meets Dr. Patrick Sullivan (who was a tall/lean/athletic Animal Doctor who was portrayed as smooth with the ladies). The actress who plays the mom is different and acts different in this movie as well.
The third film the Patrick and Jackie/Mom are portrayed by different actors/actresses. Andrea also gets older/ages from being 4 to around 11.
4th Film Patrick becomes the fat guy from Tool Time/Home Improvement. Jackie goes back to being the actress in the second movie. No mention of the Frahm kids having played soccer in the previous film or mention of the Putters or Molly. There were 4 Adult retrievers who could have been Buddy's kids in the previous film but it was never officially confirmed.
5th Film, baby Noah goes from being a baby to being around 2 or 4. Also Andrea's actress change and go from being more of a tomboy to being a girly girl. No mention of the puppies, Molly, The Putters or Josh or Andrea having played soccer.
Air Buddies, there are 5 puppies, Molly now belongs to Henry (Noah's friend/token black kid in a fairly white town) and lives across the street instead of a few blocks away). Noah is aged from being a toddler to being around Josh age in the first film. No mention of the Putters. Also Andrea's age is accelerated/she is mentioned as having gone to college after only being in Junior high in her final appearance.