one going on sixteen...

When do the pre-teen years start? Age one? Seriously. My daughter has a pre-teen attitude already. When you tell her "no", she says "ahh", flaps her hand at you, and walks off with a strut. A serious strut. Excuse me? When I tell her "no", she runs off to daddy (she's quite the daddy's girl). When Mike tells her "no", she pouts with the big, fat lip and all. I know girls are smarter (and I know this cause I am one), but this is a little too much. She's already stomping off when she gets mad and she raises her little voice in a "right-back-at-ya" tone. I have a feeling the "terrible two's" are going to start early and end at age 18. Help.