There was a previous Q&A about the Dunstan Baby Language which you can find here.

Hey Clay,

We bought the DVD and watched it b4 our boy was born, we watched it and watched it and we watched it again after he was born.   I have to say it didn't work for us, we tried really hard to decipher what he was saying but couldn't.   As you probably already know she gives you a few words that your baby will say eg: Neh meaning hungry, then she shows babies saying the word.  All good in theory and it may work for you but it didn't for us.  We just got to know what our baby was saying in his own way.   Good Luck!