Newborn Fourth Week Guide
Your baby's fourth week: First social smiles, improved head control, and emerging personality
Week 4 Major Milestones
First Social Smile
- • Genuine smiles in response to faces
- • Different from reflexive smiles
- • Usually appears between 4-6 weeks
- • Triggered by familiar voices and faces
Improved Head Control
- • Can lift head 45° during tummy time
- • Holds head steady for brief moments
- • Better neck muscle strength
- • Can turn head from side to side
Feeding Patterns - Week 4
| Feeding Type | Frequency | Amount/Duration | Notes |
|---|---|---|---|
| Breastfeeding | 7-10 times/day | 20-40 minutes | More efficient feeding, may go 3-4 hours between feeds |
| Formula | 6-8 times/day | 3-5 oz per feed | Longer stretches between feeds, especially at night |
Good news: Many babies start to have slightly longer feeding intervals and may sleep for longer stretches at night.
Sleep Development - Week 4
Sleep Patterns
- • Total sleep: 14-16 hours per day
- • Longest stretch: 4-6 hours at night
- • Daytime naps: 3-4 naps of 1-3 hours
- • Wake windows: 1-1.5 hours
Sleep Improvements
- • Beginning to consolidate nighttime sleep
- • More predictable sleep/wake cycles
- • Better distinction between day and night
- • May sleep longer after evening feeds
Physical Development & Motor Skills
Head & Neck
- • Lifts head 45° during tummy time
- • Better head control when held upright
- • Can turn head to follow objects briefly
- • Less head lag when pulled to sitting
Arms & Hands
- • Stronger grip reflex
- • May swipe at objects
- • Hands starting to open more
- • Brings hands toward face
Legs & Body
- • Stronger kicking movements
- • Better muscle tone overall
- • Can push feet against surfaces
- • More coordinated movements
Sensory Development
Vision
- • Can focus on objects 8-15 inches away
- • Tracks moving objects with eyes
- • Prefers high contrast patterns
- • Shows interest in faces and bright colors
Hearing & Communication
- • Recognizes familiar voices
- • May turn toward sounds
- • Makes more varied vocalizations
- • Beginning to 'coo' sounds
Social & Emotional Development
Emerging Social Skills
Social Interaction:
- • First genuine social smiles
- • More sustained eye contact
- • Shows preference for faces
- • May quiet when spoken to
Communication:
- • Different cries for different needs
- • Beginning cooing sounds
- • Responds to familiar voices
- • Shows contentment after feeding
Growth Expectations
Typical Growth by Week 4
- • Weight: Back to birth weight + 450-900g more
- • Length: 1-2 inches longer than birth
- • Head circumference: 1-1.5 inches larger
- • More filled-out appearance
Physical Changes
- • Umbilical cord stump usually fallen off
- • Skin less wrinkled and blotchy
- • Hair texture may be changing
- • More alert and responsive expressions
Essential Care Tips
Encourage Social Interaction
Talk, sing, and make faces to encourage those first smiles. Respond to baby's attempts at communication.
Tummy Time
Increase tummy time to 3-5 minutes several times daily to strengthen neck and shoulder muscles.
Sleep Routine
Start establishing gentle bedtime routines with dimmed lights and calm activities.
Stimulation Balance
Provide gentle stimulation but watch for overstimulation cues and allow quiet time.
Common Concerns & Solutions
6-Week Growth Spurt Approaching
Around 6 weeks, another growth spurt is common. Some babies may show early signs around 4-5 weeks.
Prepare for: Increased feeding frequency, more fussiness, and temporary sleep disruption.
Not Smiling Yet?
Social smiles typically appear between 4-8 weeks. Some babies are just developing at their own pace.
Keep trying: Continue talking, singing, and making eye contact. The smiles will come!
Sleep Regression
Some babies experience temporary sleep disruption around 4 weeks due to developmental changes.
Stay consistent: Maintain routines and be patient as baby's nervous system develops.
Approaching One Month: What to Expect
As you approach the one-month mark, your baby will become increasingly interactive and alert. The first month is a huge milestone for both baby and parents!
When to Contact Your Pediatrician
Urgent Signs:
- • Fever over 100.4°F (38°C)
- • Difficulty breathing or blue lips
- • Persistent vomiting or inability to keep feeds down
- • No wet diapers for 12+ hours
- • Extreme lethargy or difficulty waking
Developmental Concerns:
- • No visual tracking by 6 weeks
- • Not responding to loud sounds
- • Poor muscle tone or excessive floppy movements
- • Significant feeding difficulties persisting
- • Any behavior that concerns you