4 Months

Four months. You’re a parent now.

Not a “new parent,” just a parent. You’re sleeping in longer stretches, reading your baby’s cues without thinking, and you’ve been peed on more times than you can count. You don’t even flinch anymore.

Then somewhere around 14 to 16 weeks, the sleep falls apart. The books call it a regression. Your friends call it a regression. It isn’t one, but your baby’s brain is upgrading, and once you see how, those new wake-ups make a lot more sense.

Your visit at a glance

What we’ll do

• Measure weight, length, head circumference
• Physical exam
• Second round of vaccines.

Vaccines today

One combination shot (Vaxelis) covers DTaP, Hib, IPV, and Hep B. Plus PCV20 (pneumococcal). Plus Rotavirus by mouth, not a shot. So two shots and one oral dose again today.

Screenings we’ll review

• Development
• Parental wellbeing

Bring with you: A rough sleep log if you can (sleep is going to be a big part of our conversation this visit), your top 3 questions, a comfort item for after shots.

A quick note on today’s vaccines: Same crew as the 2-month visit, so you know the drill. Feed during the shots if you can, expect a fussy or sleepy 24 hours, and use acetaminophen if needed (dose by weight, and our dosage calculator will do the math for you). Call us for a fever above 104, inconsolable crying for more than 3 hours, breathing problems, or anything that feels “off.”

What’s happening at this age

Body

They’re holding their head steady, rolling tummy to back, sitting with support for longer stretches, and reaching for everything in sight. Their mouth is the most sensitive part of their body, so that’s how they explore the world now. Drooling now is because of the stimulation and normal salivary gland development. Most first teeth don’t arrive until 6 to 10 months (anywhere from 3 months to a year is normal), so they’re probably not teething yet.

Brain

• Long vowel coos (“oooo,” “aahh”), responsive sounds, and turning toward your voice
• Babbling: more vowels first, then consonant-vowel pairs like “ba-ba” and “ma-ma” closer to 5 to 6 months
• Following your gaze
• First little chuckles, with big surprised belly laughs coming over the next couple of months

Behavior

Sleep changes between 14 and 16 weeks, with more night waking. It’s a real shift, not a setback (full explanation below).

🌿 Mind / Body / Spirit, for your keiki

🌟 Is my baby having a sleep regression?

Around 14 to 16 weeks, your baby’s brain reorganizes how it sleeps. They move from long, deep newborn sleep sessions into cycles with brief wakings between them, like how adults sleep. The “problem” is that adults learned to fall back asleep between cycles, but your baby hasn’t yet. It’s actually a developmental upgrade with a slight learning curve. Real sleep training (if you choose it) becomes appropriate now. We’ll talk about the options that fit your family at the visit.

When do I have to ditch the swaddle?

The moment your baby shows any sign of rolling, even an attempt, the swaddle has to go. Once arms are free, baby can roll back to safe position if they end up tummy-down. Transition options: sleep sack, arms-up sack, or “cold turkey” (most babies adjust in 2-3 nights, faster than you’d think).

How can I understand my baby’s transitions better?

The Wonder Weeks, a framework many parents find reassuring, maps the “mental leaps” your baby moves through in the first 20 months. Leap 3 hits right now (smooth transitions), and parents often describe this stretch as “I thought we were past the fussy weeks?” Knowing the pattern doesn’t change the fussiness, but it should change the panic.

How do I know if my baby is ready to start eating solid foods?

You may start asking around now about starting solids, and the answer is almost, but not yet. The American Academy of Pediatrics recommends starting solids around 6 months. The readiness signs to watch for between now and then: sitting with little support, head control, tongue-thrust reflex fading (no more pushing things out of their mouth automatically), and real interest in your food (notice drooling and reaching). We’ll go deep on solids at your 6-month visit!

Milestones Check-In

Tracking your baby’s milestones is easier than ever with two great apps/websites, the CDC Milestone Tracker and Pathways.org.

💗 Family / Community, for you and your ʻohana

🌟 What resources can help me figure out childcare for my baby?

PATCH Hawaii is a free, state-supported resource & referral agency and a good starting point (see local resource below). Hawaiʻi has the highest cost of living in the country and one of the tightest childcare markets. If you’re returning to work in the next few months and don’t have care lined up, now may be the time to tackle the task. Waitlists at the most popular centers are 6 to 12 months long (or longer than that, if you can believe it).

Family Child Care homes (licensed in-home care) are often a wonderful alternative with shorter waits and lower cost. There’s no perfect choice, but there is one that fits your needs and this season of your family’s life.

My baby is so squirmy now! How can I still read to them?

Even though they’ll be wiggly and distracted, we recommend continuing to read early and often. Reading looks different at 4 months. Your baby will swat at the pages, try to eat the corners, and watch your face more than the book. Your voice, rhythm, and face are the curriculum. Board books with high-contrast images, faces, and texture (touch-and-feel) are the sweet spot right now.

Your wellbeing is still part of every visit

Parent wellbeing at 4 months: the ground shifts right as you find your footing. You finally feel like you know what you’re doing. You read the cries, move on autopilot, and stop flinching. And then the sleep falls apart and, for a lot of families, leave ends and you’re handing your baby to someone else and going back to work, all in the same few weeks. Feeling wrecked right now isn’t backsliding. It’s a hard season stacked on a hard season.

Signs worth attention: exhaustion that outlasts the sleep regression, anxiety or a racing mind (especially about childcare, work, or leaving your baby), irritability or a short fuse that isn’t like you, dread about going back, resentment or numbness, pulling back from your partner or friends, harsh self-talk, or a low mood that won’t lift. Postpartum depression and anxiety can emerge any time in the first year, not just the early weeks, and 3 to 6 months is a common window.

What helps at this stage: therapy, and not only in a crisis. Honest talks with your partner about who carries what, the return-to-work and childcare logistics included. Real friendship, more than texting. A few hours to yourself without guilt. Sleep and movement where you can find them, even in scraps. You can retake the Edinburgh self-screen anytime. If you’re feeling off and you’ve been waiting for it to pass, that’s the signal to call.

Crisis resources: 988 (call or text), Hawaiʻi CARES 808-832-3100, Postpartum Support International 1-800-944-4773 (they support beyond the postpartum year). You don’t have to wait for a crisis to seek support.

Postpartum Depression in Fathers & Partners. We’re now in the peak window (3 to 6 months) for partner postpartum depression. If your partner has been withdrawn, irritable, working late more than usual, or just off, share this article and start the conversation. We’re here to help.

Local Oʻahu resources 🌺

🌺 PATCH Hawaii

Hawaiʻi’s state-supported childcare resource and referral agency. They maintain real-time listings of licensed care across the island, can help you understand subsidies you may qualify for, and offer free guidance on what to look for at center visits.

🚨 When to call us

For a baby 3-6 months old, call us right away for any of these:

• Fever 101°F (38.3°C) or higher, rectal, or any fever where your baby looks unwell, lethargic, or won’t feed. (The under-3-month “any fever is an emergency” rule has eased slightly, but your gut still wins. If unsure, call.)
• After today’s vaccines: fever ≥104°F, inconsolable crying for 3+ hours, breathing problems, swelling beyond the injection site
• Refusing to feed for 8+ hours, or noticeably fewer wet diapers (less than 4-6 in 24 hours)
• Breathing that’s fast, labored, grunting, or with chest pulling in
• If your baby has stopped doing things they were doing: no more babbling, no more eye contact, no more interest in your face
• Forceful or projectile vomiting after feeds (different from regular spit-up; when in doubt, call)
• A fall from any height that ends with a head bump, any seizure-like movement, or loss of consciousness
• Your gut says something is wrong. Call. That’s what we’re here for.

📞 Call us when you need us: 808-600-2180

During office hours, you’ll reach our team. After hours, call the same number and select option 1 for our after-hours line (Hello Pediatrics), who follow our medical protocols.

For anything life-threatening, call 911.

What’s ahead in the next two months

The stretch between 4 and 6 months is when your baby goes from having opinions to definitively having a personality.

Babbling emerges next: repeated consonants like “ba-ba-ba” and “ma-ma-ma” that aren’t quite words but are getting closer.

Your baby will reach for everything, especially the things you don’t want them to, and definitely your hair. A more predictable nap pattern may start to form.

Closer to 6 months, you may see the first signs of solid-food readiness (watch for the signs we covered above).

Your baby might start to recognize their name and notice the “strangers” who aren’t you.

Enjoy the giggles for now and admire your own progress. Four months ago you couldn’t tell the hungry cry from the tired cry, and now you can, sometimes before your baby even works up to it. See you at the 6 month check!