My baby's development: Month 4

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My 4-month-old baby: a sound foundation

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 help protect her from diseases.

4-month-old baby sleep patterns and tips
  • Your baby might be sleeping about 12 to 15 hours total every 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.
How nutrition can help build your baby's immune defenses

How nutrition can help support your baby's immune system

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 is 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.

Breastfeeding is the best way to build your baby's immune system. If you choose to formula feed, Similac® Advance® provides complete nutrition for your baby's first year and supports his developing immune system.

Source: Infant Nutrition and Feeding: A Guide for Use in the WIC and CSF Programs

Baby health: Keep up on the checkups

Well-baby visits to the pediatrician are probably part of your monthly routine by now. These visits are important for you and your 4-month-old 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 the time when your baby will get the immunizations she needs (and make up any she might have missed).
  • The organisms that cause some childhood diseases have not disappeared. Regular vaccinations are still the only way to protect your baby — now and for years to come — so be sure to get your 4-month-old baby immunized to help keep her healthy.
Helping your 4-month-old baby develop language skills

Helping your 4-month-old baby develop language skills

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.

4-month-old baby developmental milestones

Every 4-month-old baby develops at a different rate. You should not be concerned if your baby does something later or earlier than other babies around the same age. Here is a general list of what your baby might be able to do around her fourth month:

  • Roll from the stomach to the back, or vice versa
  • Bring both hands together
  • Laugh out loud
  • Look for the source of sounds
  • React to a room's surroundings
Keep learning about your baby's development every week
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