what should I do

. I currently know a 17 year old due in May and is hiding it from everyone (the only reason I know is because I'm also pregnant) she's still drinking, smoking weed, having sex with random guys that don't know she's pregnant.. I know it's none of my business but I feel terrible for the child and don't know what to do. She has no money or job and has yet to get anything for the baby. I really am just sad for her, and now I come to find out she's actually dating a guy she's sleeping with and he still doesn't know she's pregnant. 🙄 I'm worried. 
UDATE:
I have tried messaging her multiple times. I have texted her best friend who has told me she's worried about her. I'm confused how I sound like I'm bashing her? I'm actually worried. And I guess she doesn't even know who the dad is? She is getting serious with this guy. And she's around 25 weeks, some people just don't start showing. And I'm sorry but it isn't normal to not try and save up money. Especially when you're teen mom. Not to mention she already knows the sex and hasn't even bought one thing. I'm not bashing her, I'm actually concerned. I got most my items right when I found out the sex of my baby. I guess some people are different.