I bought the book when DS4 had just turned 2. It was recommended on a forum like this that I had gone on. I was so excited to see that my son seemed to fit in somewhere, and I could relate so well to the stories and funny/cute little things that other kids were doing. It was hard to put him at a level at that point, but everything he was doing by age was a solid level 4, a 5 in some areas. While I was excited to see some validation and some answers as to why he was the way he was...I was suddenly aware that there were problems that could come from a child like him and that there were LOG's that I was not aware of before. And that with higher levels came some more challenges. So with the excitement of more understanding came the reality of the challenges ahead. It's also pretty funny because I remember thinking to myself when he was two...wow he is doing all this now so early...but a few things I thought there was no way he would be doing at 3 or 4. And then he did. It's been very interesting to see and fun to look back at the book while he gets older. While I don't take everything in there as complete absolutes, it's a great guideline and has helped me to realize that my child is most likely HG+ and I need to stop denying that.