@alltimemarr said:

that they find Penny, and she takes in the cat along with the dog!!! Wouldn't that just be a happily ever after? <3

A happy ending: Penny with Bolt, Rhino and Mittens.

And I loved this song in the movie: https://youtu.be/acOzVCdUSuo

A beautiful song: "Barking at the moon" by Jenny Lewis.