Definition

Typical 4-month-old infants are expected to develop certain physical and mental skills. These skills are called developmental milestones.

Alternative Names

Normal childhood growth milestones - 4 months; Childhood growth milestones - 4 months; Growth milestones for children - 4 months; Well child - 4 months

Information

All children develop a little differently. If you are concerned about your child's development, talk to your child's health care provider.

PHYSICAL AND MOTOR SKILLS

The typical 4-month-old baby should:

• Slow in weight gain to about 20 grams (almost two thirds of an ounce) per day or 1 and a third pounds (600 grams) per month
• Weigh 2 times more than their birth weight
• Have almost no head droop while in a sitting position
• Be able to sit straight if propped up
• Raise their head 90 degrees when placed on their stomach
• Be able to roll from front to back
• Hold and let go of an object
• Play with a rattle when it's placed in their hands, but won't be able to pick it up if dropped
• Be able to grasp a rattle with both hands
• Be able to place objects in the mouth
• Sleep 9 to 10 hours at night with 2 naps during the day (total of 14 to 16 hours per day)

SENSORY AND COGNITIVE SKILLS

A 4-month-old baby is expected to:

• Have well-established close vision
• Increase eye contact with parents and others
• Have beginning hand-eye coordination
• Be able to coo
• Be able to laugh out loud
• Anticipate feeding when able to see a bottle (if bottle-fed)
• Begin to show memory
• Demand attention by fussing
• Recognize parent's voice or touch

PLAY

You can encourage development through play:

• Place the baby in front of a mirror.
• Provide bright-colored toys to hold.
• Repeat sounds the infant makes.
• Help the infant roll over.
• Use an infant swing at the park if the baby has head control.
• Play on the stomach (tummy time).
• Avoid television and other screen time until age 2 years.

References

American Academy of Pediatrics Committee on Practice & Ambulatory Medicine. 2024 Recommendations for preventive pediatric health care: Policy statement. Pediatrics. 2024;154(1):e2024067201. PMID: 38910527 pubmed.ncbi.nlm.nih.gov/38910527/.

Marcdante KJ, Kliegman RM, Schuh AM. Normal development. In: Marcdante KJ, Kliegman RM, Schuh AM, eds. Nelson Essentials of Pediatrics. 9th ed. Philadelphia, PA: Elsevier; 2023:chap 7.

Onigbanjo MT, Feigelman S. The first year. In: Kliegman RM, St. Geme JW, Blum NJ, et al, eds. Nelson Textbook of Pediatrics. 22nd ed. Philadelphia, PA: Elsevier; 2025:chap 23.