It seems to hit the kids at a later date. The grief may not manifest itself in the way that we would expect either. It may come about as defiance, rudeness, being unmotivated, getting in trouble in school, nearly anything.
Kids dont necessarily grieve the same way we do. Not to alarm you Deva, just thought I would share what I have found.
I cried when Biscuit closed her eyes, shit, the Vet even teared up.