How is Shmuel Changing?

I think Shmuel is just becoming more disillusioned. He is losing all sense of innocence. After Lt. Kotler beats him, Shmuel retreats into himself. For almost a week, Shmuel does not come back to meet him at the fence. When his friend finally returns, his face is covered in bruises. When Bruno asks about his injuries, Shmuel says it doesn't hurt anymore. Bruno apologizes for letting him down and says he's ashamed of himself. Shmuel smiles and forgives him, lifting up the fence so that they can shake hands beneath it. It is the first time the two boys have ever touched.