The dog looks so utterly happy, doesn't he? 
Mmmmmmmm-hm. Sure he does. I bet that picture could prove inspiration for a shape-changer!Ennis fic.

Or the dog might somehow be imbued with Ennis's spirit. A little mountain mysticism.....

Then again, the doggie's probably just naturally drawn to Jack, because
everyone is.
Don't quite know how to tie this back to SoG.... unless the picture is somehow symbolic of SoG Ennis and Jack's eventual new life together under the witness protection program.