this is Edward "Teddy" Sheean, he was killed in the Arafura Sea on the 1st of December 1942 (age 18) in an act of heroism when the ship he was assigned to, the HMAS Armadale was attacked by Japanese aircraft attacked and sunk. He defended his shipmates from Japanese planes by strapping himself to the aft Oerlikon 20mm Anti aircraft cannon and distracted the planes, he died in the sinking.
In 1999 the fifth Collins Class submarine was named in his honour and then was awarded the Victoria Cross on the 12th of August 2020.