Let's play the Guess Which One Is Gamble game!
Let's start with eliminating who it's not. The guy on the far left standing clearly is comfortable with his father, the coach behind him, giving him a quick goosing. So that's not Gamble because Gamble has never achieved the level of happiness in that child's face, even during particularly rough anal sex.
It could be the kid squatting on the far left, who seems to be bigger than several of the kids who are standing but also willing to take a subservient role like a little bitch. There's the two kids who are straight up kneeling, too.
But my guess is Gamble is the kid awkwardly covering his tiny dick, already shriveled because he's become addicted to his first drug, Icy Hot, which he rubs all over his scrotum and penis every night before bed to let the pain help him forget his real-world failures.