<human>: Can you provide a brief overview of the text?

As the title says she was unresponsive. She drinks every weekend but today was her birthday. When she got to the hospital she had a BAC of .3 I am her 18 year old brother. How can i approach her to inform her that she has a problem and that she needs help. A little background on our relationship. Growing up all we had was our mother for the most part. She had her dad in some part and I didn't have mine. She was very violent as a child. I would constantly have bruises from her and we have almost called the police for her actions. Her father has been to jail a few times and was/is a pot smoker and heavy drinker. She's met and lived with her dad a few times. These days our relationship isn't violent in any way.
<bot>: sister drank til she was almost in a coma, what can i as her 18 year old brother do to prevent this from happening again?