“There's a stone I had made for Luke at the top of the hill road, where the pasture opens wide and the setting sun highlights the words carved into its face. "That'll do, Luke, that'll do." The words are said to working dogs all over the world when the chores are done and the flock is settled: "That'll do dog, come home now, your work is done." Luke's work is done too. He took my heart and ran with it, and he's running still, fast and strong, a piece of my heart bound up with his, forever.”
Source : Patricia McConnell, Ph.D. (2009). “For the Love of a Dog: Understanding Emotion in You and Your Best Friend”, p.249, Ballantine Books
