STERLING, Va., Feb. 8, 2007 – Marissa Strock and Jake Kessler sat in adjacent wheelchairs while prosthetic specialists attached carbon-fiber feet to their titanium legs. Army Staff Sgt. Jake Kessler ties a figure-8 knot into his harness rope as he prepares to climb a 50-foot rock with the heels of his prosthetic feet Feb. 2 at Sport Rock Indoor Climbing Center in Sterling, Va. Photo by William D. Moss '(Click photo for screen-resolution image);high-resolution image available. Strock, a 21-year-old Army private first class, and Kessler, a 36-year-old Army staff sergeant, are double-leg-amputee Iraq war veterans who forged a friendship at...