Good pondering there HP.
Her being pregnant would certainly generate some sympathy - and the friends who have been blogging on her behalf would have brought it up, maybe???
Is there any possibility that she didn’t kill Kyron, or hand him off to a third party, but just abandoned him in a place where he couldn’t get home by himself or call for help? Do we know if he ever had a cell phone?
I didn’t finish that paragraph. i.e. if she just abandoned him to wander around lost and disoriented (Sauvie Island) - when he is finally found: there will be no evidence of foul play. It will just look as if he ran away from school.