First Smiles: your baby at 4 to 6 weeks
Somewhere in these two weeks a smile arrives that is meant for you.
At 4 to 6 weeks most babies sleep 14 to 17 hours a day, feed 7 to 12 times, and stay awake for roughly 45 to 90 minutes at a stretch. The first real social smile often appears around 6 to 8 weeks. Crying is usually close to its peak, and early cooing sounds may begin.
This is a stage where two opposite things happen at once. Babies become more socially responsive, holding eye contact longer and starting to make vowel sounds, while total crying climbs toward its natural peak. Both are normal and both are temporary. Many babies also hit a growth spurt around six weeks, which can briefly raise feeding and unsettle sleep for a few days.
First Smiles at a glance
Typical ranges for 4 to 6 weeks. Every baby moves at their own pace.
| What | Typical range |
|---|---|
| Age range | 4 to 6 weeks |
| Typical sleep | 14 to 17 hours in 24 hours |
| Wake windows | about 45 to 90 minutes |
| Feeds per day | 7 to 12 |
| Longest sleep stretch | often 3 to 4 hours, sometimes longer |
| Social smile | commonly around 6 to 8 weeks |
| Typical crying | 2 to 3 hours a day, near its peak |
| First sounds | cooing and vowel sounds may begin |
What may be happening
Body
- Many babies can lift their head briefly during tummy time by around six to eight weeks, though it usually still wobbles.
- Fists are often still clenched, but hands start finding their way toward the mouth for self soothing.
- Arm and leg movements become a little smoother and less jerky as voluntary control begins to replace pure reflex.
- Growth stays fast, with around an ounce a day a common average through the first month or so.
Brain
- Eyes track a slowly moving object more reliably than a few weeks ago, though not yet smoothly across the whole midline.
- Faces are still the strongest visual pull, and babies tend to lock onto eyes and the hairline before anything else.
- Some babies begin making vowel sounds like ah and ooh alongside crying, which is the beginning of cooing.
- Many babies quieten, still or brighten at a familiar voice, showing they are matching a sound to a person.
Connection
- The first true social smile, given in response to your face or voice, commonly arrives around 6 to 8 weeks.
- Crying is typically near its peak in this window, often 2 to 3 hours a day spread unevenly.
- Evening fussiness that clusters between late afternoon and bedtime is very common at this age.
- Babies begin to hold your gaze for longer before turning away, and turning away is how they manage a stimulating moment.
Sleep at 4 to 6 weeks
Total sleep is still around 14 to 17 hours, but it is starting to organise. Some babies begin taking a slightly longer first stretch at night, often 3 to 4 hours, while daytime naps stay short and variable. Awake stretches now often run about 45 to 90 minutes. Wake window figures are practitioner guides rather than medical standards, so treat them as a rough shape and follow tired signs such as glazed staring, yawning and sudden fussing.
| Sleep | Typical range |
|---|---|
| Total sleep in 24 hours | 14 to 17 hours |
| Longest stretch | often 3 to 4 hours, sometimes longer |
| Naps per day | 4 to 6, usually irregular |
| Wake window | about 45 to 90 minutes |
| Day and night rhythm | beginning to emerge in some babies |
Feeding
Feeding frequency starts to ease slightly for some babies. Breastfed babies often feed 8 to 12 times a day at six weeks, moving toward 7 to 9 times by one to two months. Formula fed babies commonly take 3 to 4 ounces every 3 to 4 hours, rising toward 4 to 5 ounces around two months. A growth spurt near six weeks often brings a short run of extra feeds before things settle again.
- Feeds tend to get shorter and more efficient at this age rather than less frequent.
- At least 6 wet nappies a day remains the simple daily check on intake.
- Stools often become less frequent in breastfed babies from around 4 to 6 weeks, which can be normal if your baby is comfortable and gaining.
- Small spit ups after feeds are common and usually not a problem when weight gain is steady.
Questions parents ask
When do babies start smiling for real?
The first true social smile, meaning one given in response to your face or voice rather than wind or sleep, usually appears around 6 to 8 weeks. Some babies smile socially a little earlier and some closer to ten weeks. It tends to show up first thing in the morning, when a baby is well rested and you are close and face on. If there is no social smile by around 3 months, raise it at your next check.
Why is my 6 week old crying so much?
Six weeks is close to the natural peak of infant crying. Crying tends to rise from about two weeks, peak near 6 to 8 weeks, then fall away from around three months. Two to three hours a day sits within the normal range in this window, and it often clusters in the late afternoon and evening. If crying runs to three or more hours a day on most days, ask your doctor about colic.
How long should a 5 week old stay awake?
Around 45 to 90 minutes is the commonly cited range at five weeks, including the feed and a nappy change. These numbers come from sleep practitioners rather than pediatric bodies, so they are a rough shape rather than a rule. Tired signs are the better guide: glazed staring, yawning, jerky movements, turning away from your face, or fussing that starts for no clear reason.
Do babies have a growth spurt at 6 weeks?
Many do. Growth spurts are commonly described around 7 to 10 days, 3 weeks and 6 weeks, and again later in the first year. During one, a baby may feed far more often, sleep less predictably and seem generally unsettled for a day or three. It usually passes on its own. Feeding on demand through it is the standard advice, and supply generally responds to the extra demand.
Is my 5 week old too young for a routine?
Most babies are not on a clock yet at five weeks, and a fixed schedule rarely holds at this age. What often helps instead is a consistent order of events: feed, awake time, wind down, sleep. Keeping days bright and interactive and nights dim and dull supports the body clock, which generally starts to form after around six to eight weeks rather than before.
More questions about 4 to 6 weeks
The things parents actually search for at this stage. Tap any question to open it.
Why does my 5 week old cry for hours every evening?
Evening crying that clusters between late afternoon and bedtime is one of the most common patterns at this age. Tiredness and stimulation build across the day, and the peak of overall crying sits near 6 to 8 weeks. It usually eases from around three months. Three or more hours a day on most days is worth discussing with your doctor.
Is it normal for a 6 week old to hate tummy time?
Yes, most babies protest at first. Lying on the front is hard work when neck strength is still building, and a minute can feel long. Short and frequent tends to work better than long. Chest to chest on a reclined parent counts, and so does tummy time across your lap. Trying just after a nappy change often helps.
Why has my 6 week old started waking more at night?
A growth spurt around six weeks is a common explanation, and increased alertness can also make settling harder. Peak crying sits in this same window, which adds to it. Most of these unsettled runs last a few days rather than weeks. If night waking comes with poor feeding, fewer wet nappies or a fever, seek advice.
Is it normal for a 5 week old to feed every hour?
Hourly feeding in bursts, especially in the evening, is common and often described as cluster feeding. It frequently coincides with a growth spurt. What matters is the wider picture: at least 6 wet nappies a day and steady weight gain. Hourly feeding that continues day and night for more than a few days deserves a feeding review.
Why does my baby smile in their sleep but not at me?
Sleep smiles are reflexive and appear from birth, while the social smile aimed at your face usually arrives around 6 to 8 weeks. The two come from different parts of development, so one does not predict the other. Well rested, quiet, face to face moments give the best chance of catching an early social smile.
Should I worry if my 6 week old sleeps 5 hours at night?
Usually not, provided weight gain is established and your doctor or health visitor is happy. Some babies stretch to 5 or 6 hours from around 2 to 3 months, and a few earlier. Before weight gain is confirmed, most guidance suggests waking a baby every 3 to 4 hours. Check with your own clinician before letting long stretches run.
Is it normal for a breastfed baby to stop pooping every day at 6 weeks?
It can be. From around 4 to 6 weeks, many breastfed babies go a day or several days between stools, because breast milk leaves little waste. Soft stools when they do come, a comfortable tummy and steady weight gain are the reassuring signs. Hard stools, a swollen tummy, vomiting or obvious pain need medical review.
Why does my baby arch their back and pull off the breast?
Common reasons include a fast let down, wind, tiredness or simply being finished. Some babies pull off and root again within seconds. Repeated arching with crying, poor weight gain, frequent forceful vomiting or feed refusal is worth having assessed by your doctor, midwife or a lactation consultant rather than working through alone.
How do I know if my baby has colic or is just fussy?
Colic is usually described as crying for three or more hours a day, on three or more days a week, for at least three weeks, in a baby who is otherwise healthy and growing. It typically starts around 2 to 5 weeks and eases by 3 to 4 months. Only your doctor can make that call, so bring a few days of notes.
Can a 5 week old be overstimulated?
Yes. Bright light, noise, passing round visitors and long awake stretches can all tip a young baby into distress. Common signs are turning the head away, splaying fingers, arching, hiccups and sudden crying. Moving somewhere dim and quiet, and reducing rather than adding input, often settles things faster than more soothing.
Is it normal for my 6 week old to scream in the car seat?
It is common. The semi upright position, the restraint and the lack of eye contact can all be hard for a young baby, and car journeys often fall in the fussy end of the day. Keeping journeys short where possible tends to help. Never take a baby out of the seat or loosen straps while moving.
Is it normal for my 6 week old to only nap 30 minutes?
Yes. Sleep cycles at this age run around 45 to 60 minutes, and many babies surface fully at the end of one rather than joining the next. Short naps often mean more of them rather than less total sleep. The 24 hour total of roughly 14 to 17 hours matters more than the length of any single nap.
When will my baby's crying start to get better?
For most babies, crying peaks somewhere around 6 to 8 weeks and then reduces week by week, with a noticeable difference by about three months. Knowing the shape of the curve does not make it easier at 2am, but it does mean the hardest stretch is usually time limited. Persistent or unusual crying still deserves a check.
How many wet nappies should a 6 week old have?
At least 6 a day is the usual guide once feeding is established, and many babies have more. Alongside that, steady weight gain and a baby who settles after most feeds are the everyday reassurance. A drop below 6, no wet nappy for 8 hours, or unusually dark urine is a reason to seek advice.
When to check in with your doctor
Willo is a parenting companion, not a medical app. If something feels off, ask.
- A temperature of 100.4°F (38°C) or higher in a baby under 3 months needs urgent medical assessment, at any time of day or night.
- Crying that reaches three or more hours a day on three or more days a week, especially alongside poor feeding, vomiting or blood in the stool.
- No social smile, no reaction to loud sounds, and no eye contact by around 3 months.
- Forceful or projectile vomiting after feeds, green vomit, or a baby who is not gaining weight.
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Sources
- American Academy of Pediatrics. When do babies first smile?
- Nemours KidsHealth. Colic
- Nemours KidsHealth. Language Development: 1 to 3 Months
- Cleveland Clinic. Wake Windows by Age
Last reviewed 2026-08-24. Ranges are typical, not targets.
