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    Yakety-yak. She talked back!

    A smiling mother carrying a four month old infant

    Your baby’s world right now

    She’s establishing a fabulous foundation for life.
    In month four, your baby's personality has probably grown even more pronounced. By the end of the month, she might be laughing out loud and attempting to carry a conversation. Try imitating her laugh and communicating with her. This is also the time to start learning how you can start strengthening her immune system.
    An adult injecting a four month old infant with a needle

    Your baby’s nutrition

    That little body needs a lot of nutrition.
    Whether you choose to breastfeed or formula feed, your baby's immune system needs important nutrients.

    Carbohydrates, lipids, proteins, vitamins, minerals, and other nutritional compounds are important for a healthy immune system. Here’s how different nutrients can help your baby's immune system:

    • Carbohydrates, proteins, and lipids are macronutrients that supply energy, provide cell membrane structure, and promote growth and development.
    • Vitamins and minerals are essential factors in many key metabolic processes that occur in our bodies. For example, zinc plays an essential role in the normal growth and function of many cells and tissues, including immune cells.
    • Nucleotides are important substances that serve as the basic structural unit of DNA and help build and repair cells. They are especially important during times of rapid growth and development, such as infancy. Dietary nucleotides can help our body build antibodies, which are an important part of our immune defenses.
    • 2’-FL Human Milk Oligosaccharide (HMO)* is a prebiotic previously only found in breast milk. Prebiotics feed the good bacteria in the gut, where 70% of the immune system is located. And unlike other formulas, Similac has 2’-FL HMO, an immune-nourishing prebiotic that circulates throughout the body.
    While breast milk is the best nutrition for your baby, if you choose to formula feed, Similac with 2’-FL HMO helps strengthen your baby’s immune system to be more like a breastfed infant’s. Similac Pro-AdvanceTM provides complete nutrition for your baby’s first year and supports his immune system, and brain and eye development.

    *Not from human milk.
    †At significant levels.

    A four month old infant joyously laughing while being washed

    Your baby’s development

    She’s talking. Yes, indeed.
    There are several ways you can help your baby develop language skills and understanding.

    • Talk to your baby often as you dress, feed, or bathe her.
    • Provide quiet time (turning off the radio and TV).
    • Encourage your baby to turn her head toward sounds.
    • Repeat sounds often and try to get your baby to mimic them.

    Sleep patterns and tips at 4 months.
    • Your baby might be sleeping about 12 to 15 hours a day, including naps.
    • She might start rolling over and waking herself up. If possible, give her a few minutes to see if she will go back to sleep on her own.
    • Keep thick blankets, comforters, pillows, and stuffed toys out of your baby's crib.

    Have questions about SIDS?
    Learn about SIDS at the American Academy of Pediatrics.
    Doctor listening to the chest of a four month old infant

    Things to think about now

    Keep up on the checkups.
    Well-baby visits to the pediatrician are a part of your monthly routine by now. These visits are important for you and your baby because:

    • They are your opportunity to make sure your baby is growing and developing properly, and to ask any questions that might come up.
    • They are when your baby will get the immunizations she needs (and make up any she might have missed).

    Next month’s developments

    More curious, yet more cautious.
    Look forward to two-handed play, two-syllable sounds, and a healthy wariness of strangers.