Joe Costello shortly before the Battle of Ong Thanh. Joe was awarded Silver Star and Purple Heart Medals for the battle. Despite his own serious wounds, he protected and organized other soldiers who were cut off. He salvaged radio parts under fire and put together a working radio. He was able to establish contact with the command elements and supplied information to adjust artillery and other support. Joe was 18 years old at the time.
You will find more information about Joe here http://www.pbs.org/wgbh/amex/twodays/stories/st_costello.html