Baby This Week: 17 Weeks Old

Babies love to check themselves out in a mirror. In fact, faces are your baby's favorite things to see right now. Hold your baby in front of a mirror and watch her delight. She won't understand that it's her own reflection until she's about 7 or 8 months old, but she'll enjoy the view. And the motion of her hands in the mirror will capture her attention.

Researchers believe that your baby can now understand all the basic sounds that make up her native language. Between this time and 6 months of age, she'll develop the ability to make some of these sounds, which means you may hear the words you've been dreaming about, namely "mama" and "dada." While child development experts say it's too early for your baby to connect those sounds with you, that won't make hearing them any less exciting.

You can encourage your baby's attempts at communication by mirroring or imitating her expressions and sounds. She may try to imitate you, too. Say "ba" and she may try to say it back.

Reacting when your baby makes noises or tries to say something will help her learn the importance of language and better understand cause and effect. It's great for her self-esteem, too: She'll begin to realize that what she says makes a difference.

-BabyCenter.com