Moms with kids

I am a mom to a 7 year old little girl who is just like her mama she LOVES to read. She reads now at 3rd grade level. My only thing is that I feel books and even shows today the story lines are older than she should be reading. I pre read all books she gets that I feel are questionable. Do you pre read or are watch things before you allow your kids?? And any advise on books for a mature 7 yr old to read?? Thanks