That's cute, but I agree with Jules. Different states have different titles. I would say you could get her a blank white coat later to be embroidered- but three things:
1. She may not like the one you pick out
2. Vast majority of NICUs don't allow white coats due to infection control issues. At my hospital on the east coast when I worked as a nurse, there were ~20 coat hangers on the wall as you entered the NICU, just for the surgeons who did their daily rounds in the am lol, and oh boy did they know not to try to get past the nurses with a white coat on. That reminds me of the residents who also tried to unwrap our babies ahead of the surgeon team to have them "ready" for the team to look at >.<
3. Her hospital in which she will work may want their own kind of coat with their own logo and style- and will actually cover the cost. I know, I know, it contradicts with #2, however my hospital in the southwest did this and we could wear the coat when giving a presentation, conferences, etc.
Lastly- the universal credential for a NNP is: "NNP-BC" (board certified which she would be once she passes NCC exam). Other than that you have many variations of RN, APRN, ARNP, CRNP, NP, etc etc, dependent on the state in which you live.