4-Month-Old Baby Development
Summary
Average weight
6.4 kg
Average height
62 cm
Daily sleep
12-16 hours
Feeding interval
3-4 hours
Skills Gained This Month
Your baby starts rolling from their back to their side, and some complete a full roll. They reach for and grasp objects deliberately. They play with their own voice, squeal and laugh. They begin distinguishing colours and show interest in their reflection.
Feeding
6-7 feeds a day, every 3-4 hours. It is too early to think about solids this month: the recommended point is the completed sixth month. A baby watching you eat or smacking their lips does not mean they are ready.
Sleep
The four-month sleep regression is common now: sleep architecture starts to resemble an adult's, so your baby wakes more often between cycles. It usually lasts 2-6 weeks. Keeping the routine unchanged is the approach that works best.
Vaccines This Month
Around four months the second doses of the primary series are usually due — the combined DTaP-polio-Hib injection and the second pneumococcal dose. No new vaccine type is added; the series simply continues.
When To Call The Doctor
Head control still weak, with the head dropping forward when supported in sitting
Never reaching for objects or tracking them with their eyes
Constantly stiffening the legs when held upright (increased tone)
Frequently Asked Questions
How often should a 4-month-old baby feed?
A 4-month-old usually feeds every 3-4 hours. 6-7 feeds a day, every 3-4 hours. It is too early to think about solids this month: the recommended point is the completed sixth month. A baby watching you eat or smacking their lips does not mean they are ready.
How many hours a day does a 4-month-old sleep?
Total sleep at 4 months is usually 12-16 hours. The four-month sleep regression is common now: sleep architecture starts to resemble an adult's, so your baby wakes more often between cycles. It usually lasts 2-6 weeks. Keeping the routine unchanged is the approach that works best.
How much should a 4-month-old weigh?
The average weight at 4 months is around 6.4 kg, with a height of about 62 cm. These are medians; clear differences between babies are normal. What matters is steady progress along the percentile curve rather than any single measurement.
What can a 4-month-old baby do?
Your baby starts rolling from their back to their side, and some complete a full roll. They reach for and grasp objects deliberately. They play with their own voice, squeal and laugh. They begin distinguishing colours and show interest in their reflection.
Which vaccines are given at 4 months?
Around four months the second doses of the primary series are usually due — the combined DTaP-polio-Hib injection and the second pneumococcal dose. No new vaccine type is added; the series simply continues.
Log your baby's development
Track feeding, sleep, diapers and growth with one tap; let Baby Wallie handle WHO percentile charts and vaccine reminders. Free for 7 days.
Related Guides
When To Seek Care Immediately
Whatever your baby's age, seek medical care without waiting for: a fever of 38 °C or above in a baby under 3 months, a persistent fever above 39 °C at any age, laboured or rapid noisy breathing, blue lips or face, difficulty waking or marked lethargy, inconsolable persistent crying, complete refusal to feed, repeated projectile vomiting, bloody stools, fewer than 6 wet nappies a day, seizure-like movements, or the loss of a skill already gained. In these situations reach real medical care rather than an app or a web search.
This content is for informational purposes only and does not replace medical advice. Always consult your doctor or midwife about your own or your baby's health.