Baby Shower Etiquette Host

Would it be poor etiquette to host a Baby Shower for my parents’ former foster child?

She “aged-out”, but now, she’s going to have to move back in with them. She has no real family (mom moved to another state and left her). She’s only 18, in college and doesn’t have much money.
Well, were aren’t super close, but she did live with my parents for 4 years and has become like one of the family. I think of her as my “step-sister” of sorts. I fear she may not get a shower if I don’t give her one. I doubt her teenage friends have enough knowledge or money to host one for her.

Yes. Also, I WOULD call it a baby shower. It may be the only one she gets (if she doesn’t have any family around), and women like to have that memory of their “baby shower”.