My grandparents had an exchange student from Japan. They call her daughter, and she calls them "Mom and Dad", and my mother and her two siblings consider the exchange student their sister (and vice versa). I think of her as my aunt. At this point, she's been part of our family for something like 52 years. (Much longer than I've been alive, anyway.) But in this day and age? No, that's not a thing that I think happens much now.