My DD has developed quite a bad stutter, kind of out of nowhere. It first started when she was upset so we didn't think it was anything, but now she is stuttering over every sentence. She's always been ahead with her talking, she said her first word at 7 months and didn't stop from there, and she has a pretty big vocabulary for her age. I know she knows the words to use to express how she feels, because she was speaking fine a couple of weeks ago, but now she's stumbling over them. Is this normal or something we should be having checked?