Berlin, August 1961, the anniversary of the building of the Berlin Wall. With obvious apprehension, a young East German soldier glances about as he prepares to let a small boy pass through the emerging barrier. No doubt the boy spent the night with friends and found himself the next morning on the opposite side of the Wall from his family.  The soldier was seen by a superior officer who immediately detached him from his unit. “No one,” reads the inscription, “knows what became of him.”