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4 months

Your baby at 4 months

Hello, personality. She's engaged, grabby, and delighted by you — and this is often when logging starts to feel like collecting treasures rather than data.

Every baby has her own rhythm. These are gentle, typical ranges — here to reassure you and help you feel calm and confident, not rules to measure her against. Trust what you see. If something is ever on your mind, your pediatrician or well-baby nurse is always there for you.

Development this month

Milestones show up across four areas — and they arrive in any order, at her own pace.

Motorhow she moves
Communicationsounds & words
Cognitivehow she thinks
Social-emotionalhow she connects

What you might notice

Sleep around this age

Sleep is the question new parents ask most — so here's the typical shape of it, gently. Some days won't match, and that's normal.

12–15h
sleep / 24h (typical)
3–4
naps
90–120 min
wake window
7:00–8:30pm
bedtime
A sample day at 4 months

Naps start to settle into a shape. Aim for ~1h45 of awake time between sleeps.

7:00 am
Wake & milk
Wake window ~1h45
8:45
Nap 1
about 1–1.5 hours
11:45
Nap 2
after ~1h45 awake
2:45 pm
Nap 3
about 1 hour
5:15
Catnap
optional — keeps bedtime calm
7:30
Bedtime routine
bath, feed, and down for the night
Every baby's clock is her own. Shift the whole day earlier or later to fit hers — the wake windows matter more than the exact times.

Ranges based on AAP, Polly Moore, and pediatric well-baby guidance. In the app, BabyBloomy predicts her next window from her own pattern — and never pings you between 10pm and 7am.

Feeding

Still all milk (breast or formula). Some babies show early signs of readiness for solids, but there's no rush before around 6 months.

Play & connection

Play is how she learns — and the easiest logging you'll do. A few ideas for right now:

Health & safety: She mouths everything now — keep small objects away — and once she can roll, never leave her unattended on a bed or sofa. For anything that worries you, your pediatrician or well-baby nurse is the right call — never a forum.

Moments worth keeping this month

The first years disappear fast. A two-tap log now becomes a page later.

You might be wondering

What is the 4-month sleep change?

Many babies' sleep cycles mature around now and nights can feel bumpier for a while. It's a sign of development, not a step back — and it passes.

Is she ready for solids?

Some show interest, but around 6 months is the common window. Sitting with support and good head control are better signals than age alone.

Watch your effort become a memory.

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