Yes. I would add that, at least in present cultural conditions, most people who are not cisgendered men or women are not treated well, are chronically misunders

Yes. I would add that, at least in present cultural conditions, most people who are not cisgendered men or women are not treated well, are chronically misunderstood, and experience traumatic alienation from their surrounding culture, and even violence. Generally speaking we're not yet able to protect non-cis people nearly as well as we should. So in addition to the parent's clear and solid advice, please have some empathy. Respecting a person's wishes about referring to their identity can go a long way toward making them feel safe, and refusing to do so can add to a tremendous burden of pain.