Close to four months, which brings a big, normal shift in sleep as your baby's brain rewires how it sleeps. Here is what is normal.
Typical day · week 15
- Feeds: 6 to 8 milk feeds in 24 hours
- Sleep: 14 to 16 hours across day and night
- Naps: 3 to 4 naps, wake windows of 1.5 to 2 hours
- Diapers: 5 to 6 or more wet per day
Feeding
Feeding is settled, breast or bottle. Drooling ramps up noticeably around now, driven by extra saliva and an immature swallow rather than teething, which usually starts later, so keep bibs and muslins handy. Appetite, gain and diapers remain your guide.
Sleep
Close to four months, sleep often shifts as your baby's brain matures into more adult-like sleep cycles, the so-called four-month regression, which is really a permanent change rather than a true regression. If sleep suddenly worsens after a good patch, this is usually why, and it does settle with time and support. Move from swaddle to sleeping bag before rolling begins, using one-arm-out as a halfway step if needed.
Diapers
Steady output, varying by baby and feeding type.
Growth
Your baby is building the strength for rolling, which can start any time from around four months, usually tummy-to-back first. Once rolling begins, swaddling must stop. Plenty of floor time on a safe mat, rather than long stretches in bouncers or swings, supports this motor development.
This week's leap
Your baby now turns to their own name and understands far more than they can say, with a wide gap between what they grasp and what they can produce that will persist for a long while. Keep tummy time playful with mirrors, toys and your face at their level to build the strength for rolling, sitting and crawling ahead.
From three months, 101.3°F (38.5°C) or above warrants assessment; fever with a stiff neck, light sensitivity, a non-blanching rash, or a very unwell baby is an emergency. Genuine daytime pain, rather than the ordinary fussiness of the four-month changes, can occasionally mean an ear infection. If the sleep disruption is overwhelming, ask for support; gentle strategies help at this age without leaving your baby to cry. None of this is medical advice; every baby is different, and your midwife, health visitor or doctor is the person to ask about your own child.
The calm way to follow all of this is to log it in one tap as it happens, then read the pattern over a few days rather than carrying it in your head. Little Bean shows this same week-by-week guidance inside the app, beside your own baby's log.
Quick answers: 15 weeks
How often should a 15-week-old eat?
Most babies this age take 6 to 8 milk feeds in 24 hours. Feed on demand rather than by the clock; steady weight gain and enough wet diapers are the real signs intake is fine.
How much sleep does a 15-week-old need?
Roughly 14 to 16 hours across day and night. 3 to 4 naps, wake windows of 1.5 to 2 hours. The range is wide, so treat these as averages rather than targets.
What are typical wake windows at 15 weeks?
3 to 4 naps, wake windows of 1.5 to 2 hours. An overtired baby fights sleep harder, so watch the clock and the tired signs together.
Milestone reference: CDC developmental milestones, 4 months checklist.
One short note, once a month.
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