Ranting.. out of love

My sister lives 500 miles away from me so our relationship is really by text. I'm not that close to her to speak up out of fear of damaging our relationship so I just have to get this out on here.

She broke up (I say broke up bc she is still not divorced) with her husband 2 years ago and they have a 13 year old together (she's 29 and the husband is 30). I was happy for her bc she was miserable. She had her own place but apparently she was talking to this guy before she was single.

A month into their relationship she gives up her own apartment to move her and her kid into his house where he lives with 7 family members. I tried telling her not to because she would text me complaining how he won't tell her they're official. So anyway, she gets pregnant. They have the baby (14 months ago) and since then he's done nothing but cheat on her, only works enough at subway to afford his 1200$ car payment and has my sister paying ALL his bills. Mind you she makes 13$/hr so this is all her money. She took out a loan for his teeth to get fixed, financed a dog for $5,000 and financed his $1,000 phone. Now she says he's quitting his job. No plans for a new one.

Even after knowing and having proof of him cheating she doesn't leave. She tells me he treats her like crap and the house they live in has lead(LO tested positive got lead a month ago at hospital), no ceiling in kitchen, and other things. I visited her in November and told her she needs to move out and do what's best for her kids.

She couldn't even afford a toddler car seat for the little one and had to "borrow" money from him for it. She is always telling me how broke she is and he doesn't do anything or help.

SO she purposely gets pregnant. Again. Now she says how miserable she STILL is. She said he refuses to move because renting doesn't build credit, meanwhile having no plans to better himself by getting more income to buy a home.

It will be her, 2 kids, the bf, a dog, and bearded dragon all in one room.

I feel so bad for her kids and honestly don't know why she got pregnant again on purpose. I don't want her to be struggling. Although I have told her so many times it will be OK to restart again she has no plans to ever leave him.

She is being treated like a clown and I basically told her that in November. But now with adding more kids I feel like she's being overly selfish and not thinking about them at all.

She says the oldest is causing major problems and I wanted to tell her wouldn't she cause problems if her mom uprooted her and stuck her in someone's house like that? I don't blame him.

I wish she would just leave for the sake of her and her kids.