Hello! I love answering these questions b/c I am a speech-language pathologist- so I just can't help myself. Yep, it IS normal at around this age for some kids to develop dysfluencies. And yep, it is b/c they are probably going through a language development increase, and since receptive language is usually higher than expressive language at this age- when they try to put multi-words together- the mouth just can't keep up with the brain lol. Your best bet is to be as patient as possible, let her work it out- DONT interrupt if possible! Smile, give good eye contact and let her do her best. Then, when she has gotten her message out (the best she can!)- model back to her what she said with slow, smooth speech. You can either say exactly what she said- or paraphrase her message- either way, you are just "agreeing with her" as opposed to "correcting her". (For example, if she tried to tell you I want juice- and when she is done you can either say- "oh, you want juice, ok" or "ah, you said 'I want juice' good asking lets get some")
also- it IS possible that this may be an actual stuttering difficulty- and more than just developmental- usually it depends on the child's age, expressive language skills, and mostly the TYPES of dysfluencies. Obviously I can't tell you that over the internet lol- but if this doesn't seem to decrease, or if it increases to the point where she is getting REALLY frustrated- I would look into your local Early Childhood services (free at any age)- which is usually through an Infant Toddler agency before 3, and through the school district after age 3.
Here are two websites I like if you are interested in looking at more suggestions for getting through this totally normal "phase" (for lack of a better word)- and also to help you determine if you should be concerned. I like how they show the difference between the two. Hope these links work!!! And please feel free to contact me if you want! Also- sorry if my answer is long!
http://www.aboutkidshealth.ca/healthaz/Normal-Dysfluency-...
http://generalmedicine.suite101.com/article.cfm/is_stutte...
Just checked- the links work, yay!
Also thought of one more thing: if she is using a pacifier- make sure she is not trying to talk with it in her mouth ;-) and of course at this age trying to decrease pacifier use is great- but hard lol!