Why is The Heart Is Deceitful Above All Things rated R....?

I saw it was rated R, and was wondering why? Are there inapropriate scenes? if so, how inapropriate (like, what happens) I%26#039;m trying to decide if it%26#039;s suitable for my 13 yr old daughter to see.

Thank you very much!

Why is The Heart Is Deceitful Above All Things rated R....?

i saw this movie, very intense, an independent film also. The little boy in it gets raped by one of his mother%26#039;s boyfriends, has to go to the hospital to get complications from this fixed, there%26#039;s a lot of drug content, the mother is on every drug out there and says a lot of out there, vulgar things, there%26#039;s a lot of nudity, sex content, drug content, child abuse, etc. I think if you are going to let your daughter watch this movie, you should watch it with her. It%26#039;s also very depressing.