This is a tad weird. It seems as if you were expecting to smile but the strange thing is that you are sort of implying that you no longer feel as though you could control that kind of reaction which leads me to believe that you may be trying to convey that you completely lost it, at least for the time being ….
As for the best stanza or the one that stands out, I have to say that stanza 2 was the one I liked best. I surmise that your using the expression "insufficient child" gives it a strangely fascinating tone to it.
I did spot a tinge of alliteration which was nicely put down.
I would suggest though including some punctuation so as to digest the message more slowly, that's merely what I think ….
Simple. It's nice. I like the second stanza about the child and the past/future. It seems too short though, there's not much of a backbone to it...I understand that it's meant to be simple, but simple doesn't have to be short. I'm left with too many questions, about why the child deems himself to be insufficient, what's worrying him, why does he have his blank expression?
But hell, if it makes me think this much this early, it's pretty good.