The kid that caught my attention was the middle guy. He may have been about 13 (it's hard for me to tell ages). He was slightly chubby but not fat by any means, just made out of rounded and padded body parts instead of angular pieces. He wore a pair of athletic shorts that were just plain too small for his butt. Those shorts are what held my attention. Every time he stood up, he reached behind and pulled the shorts out of his crack. As he walked, the tight shorts called attention to the motion of his rounded posterior cheeks. The two sides of his ass moved up and down in opposite synch. Take a step: Left cheek goes up, right cheek goes down. Another step: Right cheek up, left cheek down. Repeat constantly; his butt kind of jiggled back and forth. The motion of his rear end was un-escapable. And from time to time he'd sneak a hand around back and pull the shorts out of his crack again.
Big bro with his car keys and air of superiority may have considered himself the main attraction, but my eyes were fixed on his bubble-butted middle brother.