I.
Name every device in the home.
Phones, laptops, tablets, gaming consoles, smart TVs, the router itself. The two of you work through the inventory lesson — usually one evening, at your own pace — and write them all down. Nothing is changed yet. Nothing is judged. The point is just to see the shape of what is actually in the house, because the cycle at 2am does not care which device is convenient.
You finish the inventory lesson with a written list, an honest picture, and no surprises waiting later.