What to do about minor sister drinking & vaping

I (24F) have a sister (12F) who been sending me videos and pictures of her drinking and vaping.

The first time it happened I called our older brother and told him immediately what I was shown and he spoke to our father about it.

For history, I am in recovery of alcohol and drugs for 2 1/2 years. Her mom is an addict and alcoholic (we have different moms) and I know her mom’s currently drinking. My sister saw her overdosing at a young age. My dad is an alcoholic and currently drinks and I believe that is how she has access to the alcohol.

She lives with my dad full time. I told my dad and he clearly has not done a single thing about this. I told her she’s going down the wrong path and I’m worried about her. She’s been through a lot and I keep telling everyone she needs therapy.

I don’t know what else I can do, but it is killing me sitting on the sidelines watching my sister become the worst version of herself. I’ve tried contacting my dad, and my brother who both live with her (I live an hour and a half away from them)

I also know posting here won’t help but I’m at work and it’s all I can think about.