I share the same concern, I am not sure you can do that after the fact. If you can, that would be the way to go, but I know the "open sleeper" ticket is an option.I'm not sure they can "just add" another pax to an existing reservation. They may have to cancel and rebook which could cause the room cost to be more than originally paid.Yes, but all of that would be the case if he just added the person directly to his sleeper reservation, anyway.Also, the open sleeper ticket when associated with the other sleeper reservation 1) allows that second passenger to have meals included in the Dining Car, 2) allows that second passenger access to the sleeping car and 3) is priced possibly lower than just buying a coach ticket. And just a coach ticket will not allow that second passenger to be in the sleeper or to have included meals. (They would need to pay in the Dining Car.)