It's really useful to understand the difference between a developmental age and a chronological age. The chronological age, of course, is how old the child is. If the child is younger that two and they are premature, you can adjust for prematurity and come up with an adjusted age. But the chronological age is where the action is at. But the developmental age is where the action is at. That is the age of the child's neurodevelopmental progress. In that age we want to think about the story of Goldilocks. We don't want to be working too high or too low but at just the right zone for the child, not depending on their age, but on their developmental stage. Teachers call this the zone of proximal development where a child is challenged just enough so that they grow but not too much so that they're overwhelmed. An example of this would be to be using extensive language for a child who does not yet have a good grasp of receptive language. To move back down for this little one to using gestures or songs or rhythm instead of spoken language to get the developmental milestones moving along and to remember that we are trying to treat the developmental age instead of exactly how old they are. It's important to make sure that the program fits the child instead of fitting a child into a preexisting program.