I am basing this on nothing more than a gut feeling. [I am the first to admit that it amounts to nothing. ] I don’t think his biological mother is involved.
I agree the school building needs to be checked and checked again. There are so many nooks and crannies.
http://www.msnbc.msn.com/id/12494679/
Missing soldier dies in hotel ductwork
Body found in air conditioning unit IDd as Iraq war vet missing for 12 days
I am not trying to be an alarmist, but if the little boy is trapped somewhere in that building, time is reaching the critical point.
That was my first thought also.