Fabio is the beloved family dog. And Fabio has it all. He has a bone to chew, a furry rug and a family that dotes on him. But Fabio is sulky and snappy because he longs for a brother. When the family decides to get a second dog from the pound, Fabio imagines all the fun he will have with his new companion. But instead of a thoroughbred brother, Fabio gets a girl!
Gracie is big and fat and old and doesn't want to play. To make things worse, the family even lets Gracie sit on the couch with them. Fabio plots to get rid of Gracie. But when the neighbourhood dogs pick on Gracie, Fabio comes to her defence because she is his sister, after all. Fabio learns to accept and love his new sister.