Robert Pilgrim is Billy and Valencia’s son. As a young adult, Robert falls in with the wrong people and participates in underage drinking, but he joins the Army and turns his life around. He even becomes a member of the Green Berets, showing that he is a particularly disciplined and successful soldier. Robert is deployed in Vietnam, but his own experiences of war don’t serve to bring him any closer to his father. While Billy loves his son, the two remain emotionally distant from each other, exchanging polite pleasantries but failing to establish a more intimate connection. This is a pattern in Billy’s interactions with all his family members. It was not uncommon for the spouses and children of WWII veterans to find their husbands and fathers emotionally disconnected due to PTSD and unresolved traumas, and Billy perfectly encapsulates this phenomenon.
Because Slaughterhouse-Five is ultimately an anti-war novel, there is something darkly comedic about the fact that Robert’s life was changed for the better by war. As a youth, he was unruly, drunk, and connected to the wrong friends, but joining the Army and the Green Berets sorted him out and transformed him into an upstanding citizen. The Green Berets are a notoriously elite and formidable force in the U.S. military, as they are trained in unconventional warfare such as guerilla tactics and espionage. It is both humorous and tragic that Billy, Robert, and society at large all agree that Robert became a better person after he’d been transformed into a trained killer.