That was my thinking. There was a companion piece to that article I linked with some quotes from Esai. He said the script had him in tears thinking of what it would be like to experience that. What else could have you in tears like that except the death of a child? Is there another Bill Adama? Does Sam Adama have a toddler aged son stashed somewhere? A younger one to account for what some consider to be an age discrepancy? Does cousin Bill watch his uncle try to resurrect his daughter and son with cylon technology? Is he raised by uncle Joseph after the mob knocks off his father? Bill was awfully quick to recognize Leoben as a cylon. Just a little too familiar in spite of what might have happened aboard the Diana 40 years earlier. For all he knew that technology never worked. How did he know
that Leoben was a cylon humanoid lifeform? A 4 year old boy in Caprica would turn 62 at the time of the later armageddon. He could have enlisted towards the end of the cylon war. It would fit. He'd still be young enough to start thinking of Joseph as a father, too.
Maybe Zoe A kills Billy. Or Tamara A.