Gretzky is a 4-year-old Pitbull in Colorado Springs, CO, who needs $2,000 for urgent leg surgery.

As a service dog, Gretzky has changed the life of his "human," a military veteran named Bill, and his two sons.

"Bill was an Army combat medic and is a proud veteran living with disabilities," Tammy S., with Victory Service Dogs, tells Waggle.

Many veterans suffer invisible disabilities in addition to those seen. Gretzky, with his loving nature, provides smiles and distractions to Bill's bouts of anxiety and depression both at home and in public.

But Gretzky recently tore his ACL. He is limping in pain and can't even go potty outside without assistance.

Gretzky can't perform his service dog duties. He tells us he'd like to get back on the job and misses helping Bill, who loves and adores him.

Will you give to help this veteran and his partner during the holidays?