To be clear: your immediate reaction to discovering, perhaps as late in the morning as 8:30 or 9:00, that your 12 year old was out and about would be panic --and you might even assume that someone had broken into your home and abducted him?
I can understand alarm and anger, I can understand you immediately calling all his friends or driving around the neighborhood looking for a butt in desperate need of a serious warming, but hysterical speechless "it must have been a homicidal maniac" panic?
Remember, we are NOT talking about the wee dark hours of the dawn. It was a bright summer morning, people have been out and about for hours, driving to work and heading to the store, the morning coffee crowd has already hit the cafes and is on their way home, kids are riding bikes and playing ball, lawnmowers and weedeaters are firing up all across this tiny little town. The morning traffic rush, what little you have of it, has already ended.
And this missing child is not an infant, she is a young teen, and this is probably HOURS later in the day than she would normally leave to walk to school -- probably alone. She is almost twelve, she goes everywhere alone, probably all over town. Mommy is not holding her hand.
So what exactly is there to be hysterical about? Alarmed... Sure! Pissed? Sure! But overcome with hysterical grief and horror? It doesn't fit. Again, and respectfully, why would a reasonable and rational adult be dumb-struck with horror?
Step dad saying "She needs to get her butt home" and posting on facebook is not alarming or suspicious, it might be callous and lax, but it's NORMAL. I can picture him rolling his eyes and saying, "Relax, the kid is out playing and forgot to leave a note. I'll kick her butt later." Celina's sister asking a neighbor is she has seen her is also normal. Calling friends is normal. Mom's reaction, assuming the neighbor's account is correct, is actually pretty weird here. WHY was mom acting this way? In my opinion, MY OPINION, the answer to this question is the answer to this entire crime.
DISCLAIMER: I am not accusing anyone of anything, nor am I advancing a theory. I am stating opinions based upon what seem to me to be logical conclusions from the very limited and admittedly unverified information available. You conclusions may vary.