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When babies are most scared, they often make no sound

For parents and grandparents of children aged 0–3
No. 326Pregnancy & KidsPart 55 of 55Fact-checked Oct 20, 2026
Video2:52 · English voice (AI) · English subtitles

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The full narration of the video.

When a baby is most afraid, they often make no sound at all. They go still and turn their face away. Their body stiffens, or they grip your shirt and won't let go. To grown-ups, it looks like being good, being shy, being clingy.

But a lot of the time, it's fear. What a baby fears changes as they grow. In the first few months, it's sudden noises, and the feeling of dropping.

Startled, both arms fly open, then pull back in. It's called the startle reflex, and it fades by four to six months. Around seven or eight months, new fears arrive: strangers, and you walking away. They've just figured out you still exist behind the door. What they don't know yet is whether you'll come back.

So how does a baby decide whether things are safe? One experiment shows it clearly. A mother sits face to face with her baby, smiling and playing. Then her face suddenly freezes. She still looks at him, but doesn't smile, doesn't talk, doesn't respond.

The baby smiles at her, reaches out, babbles. He's trying to call her back. When she doesn't come back, he turns away, slumps, and finally cries. All in under two minutes. To a baby, a grown-up's face is the sky overhead.

When it's sunny, he dares to crawl off and touch new things. When it suddenly clouds over, no rain, no sun, he can't tell whether to hide. That's the scariest part. This is the Still Face experiment. Babies read our faces and voices to decide if something is scary. It's called social referencing.

You can see it at home: he touches something new, then looks back at you. That glance is him checking the sky. Luckily, you're not like the real sky: when he cries, you can clear up right away. In the end, the mother smiles again, and most babies recover quickly.

Later work found that in everyday life, parent and baby are perfectly in sync only two or three times out of ten. What matters isn't never drifting off. It's coming back for him after you do. Day to day, that comes down to a few small things.

Before you leave, crouch down and say goodbye. Don't slip out when he isn't looking. Sneak away, and he learns you could vanish any time. Next time, he holds on even tighter. Say when you'll be back, and be back then.

When he looks back at you, give him a smile, and an "it's okay." If fear keeps him from eating or sleeping, or he still can't separate from you in kindergarten, ask a doctor, and follow their advice. Whether a baby is afraid often depends on one look at your face.

How old was your baby the first time they got shy with strangers?

1

Fear without a sound

Before you leave, crouch down and say goodbye. It is better than slipping out while your baby is not looking.

Why? Because a scared baby does not always cry. Crying is only the last step.

What adults often think
Scared means crying
What it more often looks like
Going quiet, looking away, shrinking a little, gripping your clothes

People often call this “good”, “shy” or “clingy”. Often it is one thing: fear.

2

Different fears at different ages

Birth 8 mo 18–24 mo Startle reflex Strangers, separation

Newborns are scared by sudden noises and by the feeling of falling. They fling their arms out and pull them back. This is the startle reflex. It fades by four to six months.

At about eight months, babies learn who their own people are. They hide in your arms from strangers and panic when you walk away. For most, this is strongest at 18 to 24 months, then slowly eases.

When you go behind a door, your baby knows you still exist. What they do not know is whether you will come back. How babies learn that things “still exist”: see this episode.

3

The mother’s face goes still

In 1978, the American psychologist Edward Tronick ran an experiment. A mother and baby sat face to face. First, she played with the baby as usual.

Part 1 · Playing
Part 2 · The face goes still
She does not smile, talk or move. The baby tries hard to get her back: babbling, reaching, smiling.
No answer
The baby looks away, drops their head, slumps, and only then cries.

All in under two minutes.

The mother did nothing wrong. Her face only went still, and the baby panicked.

4

The sky above

To a baby, your face is like the sky overhead.

When it is sunny, they dare to crawl out to the ball. When it clouds over, they stop. The worst is grey sky with no rain and no sun, like that still face.

The experiment is called the Still-Face experiment. Babies reading your face to decide if something is scary is called social referencing. It is also why a child who falls looks at you before crying: see this episode.

At home: before touching something new, your baby looks back at you.

5

Reconnect

The real sky does not listen to anyone. Your sky does: when the baby cries, one smile or hug and it clears. In the last part of the experiment, the mother played again, and most babies recovered quickly.

Tronick later said that parent and baby are in sync only about two or three times out of ten. Missing a cue or being distracted the rest of the time is normal.

What matters is not staying in sync. It is coming back after you drift.

6

A few small things

Say goodbyeCrouch down: “I’m going to work, I’ll be back tonight”
Don’t sneak outIf you slip away, next time they watch you even harder
Come back on timeKeep the time you promised, and they learn you return
Smile backThat look before touching something new asks “Is this safe?”
When to ask a doctor If fear stops them eating or sleeping, or they still cannot separate long after starting preschool. Follow your doctor’s advice.
Whether a baby feels safe
often starts with
a look at your face.
How old was your baby when stranger shyness first showed up?
Made by Samshang × Maddox
Sources: Tronick E. et al. (1978), original Still-Face paper, J Am Acad Child Psychiatry; Mesman J. et al. (2009), The many faces of the Still-Face Paradigm (PMC3568681); Merck Manual, “Separation Anxiety and Stranger Anxiety”; HealthyChildren.org (AAP), emotional development 8–12 months and separation anxiety; Zero to Three, “Separation Anxiety”; Families and Work Institute interview with Tronick (in sync only 20–30% of the time)
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