Jack snorted, running his thumbs gentle, yet firm, down the older Jack's spine. He could feel the knots and welts of the muscles corded to either side and felt a pang of sympathy. "Then he must have been much younger, poor thing," he grinned. "Hasn't quite grown into it yet."
He fanned his fingers on either side of Jack's spine at his lower back and followed the direction the muscles lie, massaging in gentle sweeps.