"Then she starts putting concepts together and learning grammatical rules; "
That alone requires a very large internal database (which she's been building since the day she was born).
I think the word you're looking for is "Intentionality" The desire to do (or learn, or say) something.
I think a lot of AI types spend so long on their little corner they forget that language actually evolved to do update other peoples internal database.
The early success that linguistics gave to compiler writers gave them an undeserved sense of achievement. COBOL has about 230 "rules of grammar." English more than 15 000 (incomplete and therefor ambiguous). Writing a COBOL compiler (C has about 30) without modern tools is a formidable task. But once you're written your English compiler, what does it do?