No, it is an acceptable question. Just ask politely, like you are curious and loving parent.

You know the situation better then I can possibly know. If you trust the family, good. But if you do not know anything about the family, it is your right to ask questions.

Your daughter will likely have fun. This is a common activity for American children.

Edit: by offering to provide food or help out, you are making it seem less rude when you ask the questions. 😉