Five years old but still a child

So it was my daughters birthday on Tuesday. She is now five years old. I can't believe how big she is. And today she buttoned and zipped her pants all on her own for the first time. And she is buckling herself into her car seat. Pretty soon she won't need me at all. Course right at the moment we are living with my sister-in-law and her four children and you would think that a five year old would be able to stand up for herself against her two year old cousin. I guess that it's a good thing that she doesn't want to hurt him but still I don't think that means you can't use words and tell him that you don't like what he's doing and that you won't play with him until he is nicer. Yes, we've all told her to just hit him back but she doesn't and I'm not really upset with that so much as I'm upset that she cries so much about it. I mean if you aren't willing to stand up for yourself then you'll never make it in life. We don't want her living with us when she's 30. :) Here's to hoping that she starts acting her age.