How should I approach my daughter about her Facebook account?

[Ramsey]

My daughter is in the 5th grade.She asked me if she could get a fb account. I had told her that I'd prefer her not getting a facebook account yet. This was back in the summer, so for the past few months I wondered if she had one, so I asked her several time (2 or 3 times) and she said no. Well I noticed my in-law had kinda blocked me on a few things. So I logged on to my wife's, my wife and i know each others pssword, anyway, i log on and I am browsing on my in-law's page and get to the pictures section. There is a picture of my wife and my daughter and my wife is tagged and i noticed my daughter is tagged with a name that is'nt hers. hmmm, wow! really?! So at this point i am upset, i let my wife know about this. Long story short: I am upset that after I asked not to get a faceboo account, she did anyway. I am upset because my in-law blocked me thinking i would not find out... What should I do? How should I treat this matter? What my approach? She will be grounded that much I know.

(Please no put downs or make a joke out of this.)