During the 2012 Sea Turtle Triathlon in Pensacola, a young boy's prosthetic limb broke during the run. Local Marines, who had volunteered to help monitor the course, picked him up and carried him the rest of the way to the finish line.
There weren't very many dry eyes in the crowd cheering everyone on. The Marines also helped urge on many other racers and ran with them across the finish line.
(Story from ireport.cnn.com)