Just after my son turned 8, he started developing facial tics. It would come and go, getting worse during times of excitement or stress. As time progressed, they became constant. My ped referred us to a neurologist who diagnosed him with "transient tics" which are related to Tourette's. Some of these kinds of tics are verbal. I'm not saying that his stuttering is the same thing, but it's a possibility.

We ended up putting my son on Tenex and the tics are almost gone. They still show up when he's excited, but not to the degree that it was. Also, for the first time ever, he made straight A's on his report card.

I think you should ask the doctor, especially if it gets worse.