The song "Billy Overcame His Size" by Merle Haggard tells the story of a small guy named Billy who was always overlooked and underestimated by his family and peers because of his size. His brother was the star athlete and got all the attention, while Billy was left behind. Despite this, Billy never let his size hold him back. He had a fierce determination and never got angry or bitter about being called "shorty." He joined the military, and even though the Sergeant laughed at his skinny frame, he persevered and proved himself to be a brave and capable soldier. In the end, Billy died saving the lives of his fellow soldiers, bringing pride to his father's eyes and showing that size doesn't determine bravery or strength. Overall, the song is about overcoming adversity and proving yourself through hard work and determination, no matter what obstacles may come your way.