Even if my tiny baby son was just saying ‘ah-goo’ to me, I’d smile and say something like ‘Is that right? Tell me more!’ in my normal voice, and pay as much attention to his reaction to that as I would if he’d spoken a sentence.

My son started to talk coherently at a very early age- I don’t know how much was an innate gift and how much was due to my encouragement, but I know that the transition to recognisable words was very fast. I didn’t use baby talk at all; I did use a very expressive tone.

Thank you for adding this, because I agree with most of what you say and I apologize if my meaning wasn’t clear. Yes, we must speak much slower and make our sentences briefer, so that babies can begin to comprehend our language. I wrote about that in my post: Talking To Toddlers. But, I don’t agree that we need to speak in a high-pitched voice. The studies I’ve read about that have been inconclusive, and changing pitch can feel forced and inauthentic. Infant expert Magda Gerber encouraged parents to talk to babies in a genuine and loving voice. And I believe that babies want us to be ourselves with them from the beginning, which means using our own voice, our own way of talking. Magda advised parents to “show your child you believe she can understand you.” And in Your Self-Confident Baby she wrote, “Baby talk is not our language but an artificial one created for what we think children like.”