Advice ?

I love my mother but she is very irresponsible she doesn't want to work she just wants to borrow money from my grandparents & her friends I even got her a job and she quit within the first week now her lights are about to be off and she's mad because it's stressing her out 🤦🏼 she also has an addiction to pills and god knows whatever else and I'm not sure how to help her I have a younger sister that lives with her and I hate seeing her go through the same thing I did as a child how can I help my sister ? I'm only 19 so I'm sure I can't do much legally.