What Happens to a Baby During the Third Growth Crisis
 Category | Growth crises |
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Medically reviewed by pediatrician and perinatal psychologist Polina Kizino
The third growth leap brings new impressions and the first “conversations”. Your baby starts noticing changes in light, sound, and movement, begins gazing at faces, tracking toys, and trying to babble. They may want to be held more often, seem fussier, and sleep less — it’s their way of adjusting to change. This leap usually happens around weeks 11–12, but every baby has their own pace.
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Quick takeaways
- The third growth crisis typically occurs around week 11–12.
- The brain begins to respond to changes: light, sound, and movement become more distinct.
- The first intentional eye contact appears — the baby starts “looking into” faces.
- The baby may become more anxious and seek more rocking and closeness.
- Babbling begins, along with responses to voices and attempts to “join the conversation”.
Transitions and changes — a new level of perception
Previously, the baby only noticed strong stimuli (bright light, loud noise), but now they begin to perceive gradual changes: how light brightens, how voices become softer or louder, how a toy slowly moves. This signals the maturation of the visual and auditory cortex.
The baby starts holding their gaze — following faces or toys for longer, tracking movement. This is the foundation for developing attention and control.
First steps toward emotional connection
The baby doesn’t just react to the parent's face — they begin to recognize it. Smiles become intentional, gazes focused. This is the beginning of emotional bonding and social awareness.
At the same time, babbling develops: the baby “responds” to speech, tries to imitate sounds, and pauses when hearing their name.
Behavior may change suddenly
Like every growth crisis, development brings nervous system tension. This might look like:
- frequent night wakings
- fussiness or unexplained crying
- wanting to be held constantly
- difficulty calming down
This is normal: it's part of adaptation and will pass
How to support your baby
- Speak calmly, clearly, and with pauses.
- Smile, offer soft toys with different textures and sounds.
- Hold your baby facing you so they can watch your expressions.
- Support contact through swaddling, rhythmic motion, and rocking.
- Avoid sudden changes in routine — consistency helps with adjustment.
Frequently Asked Questions About the Third Growth Spurt
When does the third growth spurt happen?
The third growth spurt typically occurs around 11–12 weeks of age. During this stage, babies become more aware of changes in light, sound, and movement.
What new skills appear during the third growth spurt?
Babies begin making more intentional eye contact, tracking faces and toys for longer, and showing early babbling. They may also start responding more actively to voices and facial expressions.
How can I support my baby during the third growth spurt?
Talk calmly, smile often, and give your baby opportunities to watch your face. Consistent routines, gentle rocking, and age-appropriate toys with different textures and sounds can help them adjust to new experiences.
Why is my baby fussier and waking more often?
As the brain adapts to new sensory information, babies can become more sensitive and easily overstimulated. This may lead to increased fussiness, more frequent waking, and a stronger need for physical closeness.
With care
Our articles are based on evidence-based medicine and reviewed by pediatricians. However, they do not replace a consultation with your doctor. Every child is unique — if you have any concerns, please consult a medical professional.
Sources
- Plooij FX, van de Rijt-Plooij H. The Wonder Weeks: How to Stimulate Your Baby's Mental Development and Help Him Turn His 10 Predictable, Great, Fussy Phases into Magical Leaps Forward. Kiddy World Publishing; 2017. ISBN: 978-9491882166
- Child growth standards, WHO, https://www.who.int/tools/child-growth-standards/standards. Accessed 7 May 2026.
- 12 month developmental milestones, UK National Health Service, https://www.cambspborochildrenshealth.nhs.uk/child-development-and-growing-up/milestones/12-months/.
- National Research Council (US) and Institute of Medicine (US) Committee on Integrating the Science of Early Childhood Development. From Neurons to Neighborhoods: The Science of Early Childhood Development. Shonkoff JP, Phillips DA, editors. Washington (DC): National Academies Press (US); 2000. PMID: 25077268. https://pubmed.ncbi.nlm.nih.gov/25077268/.
- and de Onis, M. (2006), WHO Motor Development Study: Windows of achievement for six gross motor development milestones. Acta Pædiatrica, 95: 86-95. https://doi.org/10.1111/j.1651-2227.2006.tb02379.x. Accessed 7 May 2026.
- CDC’s Developmental Milestones, U.S. Centers for disease control and prevention, https://www.cdc.gov/ncbddd/actearly/milestones/index.html. Accessed 7 May 2026.
- Toddler Developmental Milestones & Safety, Cleveland Clinic, https://my.clevelandclinic.org/health/articles/22625-toddler-developmental-milestones--safety. Accessed 7 May 2026.
- Misirliyan SS, Boehning AP, Shah M. Development Milestones. 2023 Mar 16. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan–. PMID: 32491450. https://pubmed.ncbi.nlm.nih.gov/32491450/