You should go to a therapist, they'll know what to do. But please try to be patient and let her finish her sentences. Also if she stutters it doesn't mean she's gonna have a terrible life, it all depends on 2 main factors: it basically depends all on her and the people around her. I had a similar situation as your daughter when i was younger, i was supposed to be bilingual but i soon started to have troubles speaking and the doctor said it was better if my mother stopped teaching me her language so i'd only learn my dad's one but that didn't make my stutter go away in any case so it's better e if you teach all the languages you know well. Of course i'm not an expert so i suggest you to contact a therapist somehow and let them know your situation, they'll know how to help you. Hope i helped you somehow, have a great day.