Uh, he didnt need the boy!
I haven't followed the story that closely because it's too upsetting but I was under the impression that his previous victims were male so I would assume that he'd prefer to keep the boy and get rid of the girl.
The BEST we can do in a case like this is to HAUNT the POS judge who let this scumbag off. Write him letters on how awful it must feel to be DIRECTLY responsible for this child's death . Write him til his dying day.
Actually it was the other way around. He didn't "need" Shasta (as his tastes run to little boys, in accordance to what I've read on him.) This is what makes this whole matter so mysterious. His objective would obviouisly have been young Dylan, so why Shasta didn't end up like her mother, oldeer brother and stepfather, and at the same time, are unfathomable at this point. Only he can divulge the whys, now, and he hasn't been talkative..
the infowarrior