What this article doesn't address is that the source of the traumatic experiences often are rooted in their home environments, specifically parental abuse in the first place.  So it may be more important that counselors, teachers and doctors are aware of the symptoms and signs of abuse and PTSD in children. The fact that children have no where to escape from this abuse is why you see the symptoms of numbing or disassociation, because it's a mechanism that's useful to escape unavoidable pain.