Who is Grandfather Stalking Wolf from The Tracker and what is their importance?

This is Rick's real grandfather. He is an Apache Indian, one of the last warriors trained in the ancient ways of the tribe. Grandfather Stalking Wolf has mastered the physical challenges of tracking and stalking, but more importantly understands and has mastered the spiritual ways of the wilderness. He is a master teacher, using few words but many examples, gestures, and challenges.