My DD is exactly the same. I feel that when my DD is pulling at her hair/biting etc she is actually venting her frustrations at not being able to do something (climb the fence, unlock the door etc).

I haven't been disciplining her as such but I do sit her down and explain why we have the door locked, why it isn't safe to climb the fence etc. Some people think I am crazy for explaining to a 12 month old why these things are the way that they are but she does calm down when we talk - and then of course she gets up and tries to climb the fence again

I think it is one of the stages/ages things. They are learning more about there world and that not everything they can do just now. Hope that makes sense.

These August '09 babes of ours certainly have us on our toes