I had a friend in HS who had a stutter but he played basketball, was attractive, smart and nice. I don't think he was ever in speech (we would've crossed paths at some point) but he never let it slow him down or visibly affect him. I think therapy helped me a lot, but he showed me that sometimes just a positive mindset and the right encouragement (must) go a long way. Just keep supporting her and let her know to come to you if she has issues with any other teachers. You might not be able to help directly, but you might at least validate her frustrations or whatever the case.