I saw a recent article with regards to the link between Autism and vaccines. Personally, I am not sure, my daughter especially was speaking at 6 months, and was almost potty trained at 1 year and then she had her shots and her potty training training and language development got much worse.

Here is an article from the Augusta Chronicle, that refers to a planned study to figure out if there is a link or not once and for all:

http://chronicle.augusta.com/opinion/letters/2011-03-07/let-vaccine-study-settle-autism-dispute

It is interesting and thought provoking.