I noticed that my handwriting changed as I grew older too. As a teen the letters were larger, more round and now letters are smaller. I noticed the same with my daughters. I don't have any experience in handwriting analysis, but find it fascinating. I know it's not a 100% science and opinions range depending on the expert...still I think there is something to be learned from the analysis of Casey's handwriting. I would love for a good analyst to look at the journal entry found in the home to determine the time of that entry. So far I have not found any expert opinions on this topic.
I think it would be interesting to have an analysis of all the family members.
Here is one site, I had not seen before. Many of the comments are from people who are not experts, but I thought their opinions were interesting.
http://www.viewzone.com/handwriting.casey.html