I really try not to judge victim's parents parenting style but I am so shocked by this. I just can not comprehend how any parent can allow their 6 year old on their own without a buddy let alone not worry from 2pm to 8pm. To not know if they've eaten, to not know exactly who's home they are playing at, to know that if it's sunny they have sun block reapplied, not fallen and hurt or something. I can't get my head around it. 6 years old is so, so young to fend for yourself.
I don't know about the law in the US, but in the UK it is illegal to leave a child under 12 alone at home for any length of time (and I consider 6 hours a length of time!). If a child should not be left alone in the home for that long, they shouldn't be alone outside the home for anything like that either without being supervised or at the very, very least 'check-in'.
OK rant over. I do truely feel so incredibly bad for this family and for what happened to this little girl. It's beyond comprehension. I don't blame the parents, no one should go through this. I just really wish people would think of all the dangers that children can run into. It only takes one bad thing to happen to change a child's life forever.