I seem to recall an old B&W movie about him, or that had a scene based/influenced by him.
I was recently on YouTube and stumbled across episodes of an old B&W TV series titled Combat! Not bad except all the fighting took place in the French and German desert.
In one of the episodes, a replacement in the platoon who recently distinguished himself in combat is found out to be 15 and sent home.
I don't know about an old B&W movie, but apparently a movie based on his life was made in the 1980's: Too Young the Hero
At 12, he was still a child. The lowest age I'd heard about was 14, which also was far too young.