!! First Movie
** It's more tearjerker-y if you've had dogs. ''Especially'' if you tend to project emotions onto them.
** Even more especially if you've had a dog put down or die in some way.
*** Why doesn't anybody ever write a pet memoir while the animal in question is still alive?
* TheOtherDarrin : Multiple dogs play the part of Marley, which is common in Hollywood because often each dog performs a different trick (running, chewing, barking, etc.), and because Marley is shown as a puppy, an adult, and a senior dog. However, they don't even TRY to disguise the very different looking Retrievers who play Marley, resulting in a jarringly different appearance between the adult and senior dogs.
* TheWoobie: Marley becomes one in his later years
!! ''The Puppy Years''
* SpecialEffectsFailure: Very shoddy CG used.
* TheyChangedItNowItSucks: Was obviously trying to cash in on the ''Air Buddies'' movies considering how much more childish and slapstick it is. Lacking any of the charm and heart of the previous entry.