Is this legal for her parents to do? Also, should I help her so she doesn’t fail school tomorrow because of them?

I have a 20yr old friend who owns her own car, pays her own insurance, & pays rent to her parents. She lives with them & they’ve always been pretty strict. She has a curfew of 11pm no matter what (she can’t stay at the library to study past or late at work even) & she’s never slept over at a friends house because she’s not allowed or have friends over (which is technically her parents own house rule but still a odd to never have guests). She lives with them because rent to them is cheaper than getting an apartment & they told her that if she ever moved out that they’d never talk to her ever again. She has her own job which she uses to pay for school. Her parents are of a very strict religion called Jehovah’s Witness. I don’t know a lot about it, but I have another friend from a home of it & she said her parents were the same way to her. I of course do not want to disrespect anyone’s beliefs, but it is supposed to be strict from what I have heard. Anyway, the problem here is whenever my friend does something her parents don’t like such as come home late even by 10 min she gets her keys taken away and is “grounded” from leaving the house. Since it is her car & she pays them rent is this legal? She stays with them because they tell her they won’t love her anymore if she moves out. I think it’s sad. She will possibly miss a final exam tomorrow because she is grounded, too. I want to sneak & take her to school so she won’t fail her class but I don’t want to upset her parents more.

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