Copper

Copper is a character in the Once Upon a Time novel, "Red's Untold Tale". He was the dog of Amos Slade and, following Slade's death, bonded to a village boy by the name of Peter.

Before the Curse
Copper was Amos Slade's hunting dog, often at his master's side when Red Riding Hood makes deliveries to his house. When Red makes her own cookies and they end in disaster, Slade feeds one to his dog which allows Red to realize that she can re-purpose them as dog biscuits. After Slade is killed by the wolf, the dog bonds to her friend Peter, who gives him the name Copper.