Well darn it th - would have been nice if the prednisone had increased your son's count to a decent level - how long was he on it?
Good you are getting some blood test results that are normal - hope that continues. It does seem that so many new ones here that were just diagnosed have been bombarded with many treatments all at once, the body can't like that (my opinion). Maybe it is good to hold off on treatment for a bit to see if he may rebound on his own but watch closely for symptoms. Boy it would be a blessing if his count would rebound to a decent level - fingers crossed for him!!
I've had ITP since 1989 and I certainly do not daily check for anything - I'm happy to be getting out of bed and being on the right side of the grass

And actually when my count did hit the gutter after a tetanus booster I didn't have 1 symptom, it was just a feeling that my count was low that sent me for a CBC.
Hang in the th - sounds like you are doing right by your son and that your son is handling this well.