Between about one and three months of age, your baby will reach some fun hearing and speech milestones. These include smiling at the sounds of your voices and turning their head toward the direction of sound. They'll also begin to babble and imitate some sounds.
The sound of your voice
Just as your baby naturally prefers the human face over other visual patterns, they also prefer the human voice to other sounds. They will recognize and respond to those voices they hear most. They associate them with warmth, food, and comfort. Babies like high-pitched voices in general—a fact that most adults seem to understand intuitively and respond to accordingly, without even realizing it.
Listen to yourself the next time you talk to your baby. You'll probably notice that you raise your pitch, slow your speech, exaggerate syllables, and widen your eyes and mouth more than normal. This dramatic approach is guaranteed to capture almost any baby's attention—and usually make her smile.
By listening to you and others, your baby will discover the importance of speech long before they understand or repeats specific words. By one month, they'll be able to identify you by voice, even if you're in another room.
As you talk to your baby, they'll be reassured, comforted, and entertained. When they smile and gurgle at you, they'll see the delight on your face and realize talk goes both ways. These first conversations teach her many of the subtle rules of communication, such as turn-taking, vocal tone, imitation, pacing, and speed of verbal interaction.
At about two months, your infant may begin cooing and repeating some vowel sounds (ah-ah-ah, ooh-ooh-ooh). Over the first four to six months, imitate their cooing, while adding simple words and phrases to your “conversations." It's easy to fall into a habit of baby talk, but you should try mixing your conversations with adult language and eventually phase out the baby talk. During early infancy, you should also read to your baby, even if you think they doesn't comprehend.
By four months, your infant will babble routinely, often amusing themselves for long periods by producing strange new sounds (muh-muh, bah-bah). They'll also be more sensitive to your tone of voice and the emphasis you put on words or phrases.
As you move through each day together, they'll learn from your voice when you're going to feed them, change their diapers, go for a walk, or put them down to sleep. The way you talk shows them much about your mood and personality, and the way they respond shows you a lot about theirs. If you speak in an upbeat or comforting way, they may smile or coo. Yell or talk angrily, and they'll probably startle or cry.