What is Baby Talk
Baby Talk is a concept and practice of communication with babies, using various methods of communciation. I prefer the term Baby Talk to Baby Sign which is prevalently misperceived.
The innermost idea behind "Baby Talk" is that babies can communicate conveniently in both signlan and speech (for hearing), since research shows that all stages of language acquisition exhibit the same milestones in both speech and signlan.
It is nothing new among ASL parents who have been talking with their children in ASL, like any other humans who speak different languages. It's not about sign language; it's about allowing infants (deaf or hearing) communicate different ways, for language development works the same for all languages, signed or spoken.