Not saying you're wrong, its anecdotal on both our parts. But I do! If you say to a kid "They built all of this by hand on pen and paper from ideas in their head! (amazed expression)" they'll parrot back to you the above sentence if they catch the meaning and context. My 3 year old does this already, although she'll say "fantastic" instead of "incredible".
I would agree with this. My observations after having children, is that they do exactly what they see until they understand what they see and make it their own.
For example - my youngest recently had an abscessed tooth removed. He is 5 this year. The dental surgeon was astounded that he used the words nitrous-oxide and Novocain. The surgeon said things like giggle gas and sleepy juice, and the five year old dead pan corrected him.
Kids will say what they hear - outside of a disability/difference of that kind. If they hear short baby talk, they say short baby talk. If they hear larger words, in context, often, then they'll use those.
