Give her some time. She's still little, and be happy with her. As she gets older those feelings of frustration and isolation may only increase for her - especially as she gets to the teenager years where were all angsty depressed things! The biggest thing you can give her when she's speaking is patience, and your undivided attention. I recommend reading "Advice to the Stutterer." If you Google that, The Stuttering Foundation actually had the full book in PDF form for free! It will be useful for her specifically as she gets older, but it'll also give you an idea on how she might feel and techniques she should try again, as she gets older.