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Why do toddlers
throw tantrums?

For parents of 1- to 3-year-olds
No. 339Pregnancy & KidsPart 61 of 61Fact-checked Oct 20, 2026
Video2:26 · English voice (AI) · English subtitles

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No candy, so why is your kid lying on the floor? Right at the supermarket door, he's crying and kicking, and everyone walking by is looking at you. An older relative says: this child has been spoiled.

But between ages one and three, almost every child throws tantrums like this. Spoiling isn't the root of it. The root is a machine inside his head. This machine has a gas pedal and a brake.

The gas pedal runs feelings. When he doesn't get what he wants, it slams to the floor, and anger shoots up. That gas pedal comes fully installed at birth. The brake is for "wait a second." It holds the anger back and finds another way to ask.

But the brake gets installed very, very slowly. It sits at the very front of the brain, behind the forehead, and it's called the prefrontal cortex. It grows bit by bit, all the way into your twenties.

At two, the gas pedal works perfectly, and the brake is barely started. So the smallest thing sends the car flying. One more thing holds him back: he doesn't have the words.

He's upset inside, but he can't say "I'm tired" or "I'm so disappointed." Toddlers who know fewer words tend to have more big tantrums. And when he's hungry or sleepy, the brake works even worse.

So once a tantrum starts, what's actually going on inside? Researchers took children's tantrums apart, moment by moment. They found that one tantrum is really two waves.

The first wave is anger: screaming and kicking that peak right at the start, then slowly fade. The second wave is sadness: crying and wanting a hug, rare at first, then growing toward the end. Most tantrums are over within five minutes.

Know these two waves, and you know what to do when. At the peak of anger, reasoning won't get through. The brake isn't connected yet. Stay calm, keep him from getting hurt, and say very little.

When the crying softens and he leans into you, the sad wave has arrived. Now hold him and put it into words for him: you really wanted that candy, and you're so disappointed. Every time you do this, you tighten one more bolt on his brake.

If tantrums happen many times a day, or he often hurts himself, have a doctor take a look. So when your kid rolls on the floor, it's not bad parenting. His brake is still being built. What's the silliest thing that ever set your kid off?

The one lying on the store floor

No candy, so your kid is on the floor, crying and kicking. An older relative says: that child is spoiled.

But between ages one and three, almost every child has tantrums like this. It is a normal stage of growing up, not a sign you did something wrong.

A gas pedal and a brake in the brain

Think of the emotional brain as a machine. The gas pedal is feelings: when a child doesn't get what they want, it slams to the floor and anger flares. That pedal comes installed at birth.

The brake says "wait a moment": hold the anger, try another way. But the brake is installed very slowly.

At two, the gas is full and the brake is just going in.

The brake sits behind the forehead

Age 025 Prefrontal

The brake's real name is the prefrontal cortex, the very front of the brain, right behind the forehead. It is one of the last parts to mature, growing bit by bit into the mid-twenties. That is why four- and five-year-olds are steadier than two-year-olds, yet still far from finished.

Two more things make it worse

Not enough wordsThey can't say "I'm tired" or "I'm disappointed", so they say it by crying
Hungry or tiredThe brake works even worse, so small things set them off

Toddlers with fewer words have more severe tantrums. If your child talks late, see whether grandparent care delays talking.

One tantrum, two forces

5 min Anger Sadness

Researchers broke tantrums down moment by moment and found two forces in each one. Anger (screaming, kicking) peaks right at the start and then slowly falls. Sadness (crying, wanting a hug) starts small and keeps growing.

Most tantrums are over within five minutes.

What to do, and when

WHEN ANGER PEAKS
Stay calm, keep them safe, say little.
Reasoning won't land now: the brake isn't connected yet.
WHEN SADNESS COMES
Hold them and put their feelings into words.
"You really wanted that candy, and we didn't buy it. You're so disappointed." Every time you say it, you tighten one more bolt on their brake.

If tantrums happen many times a day, or your child often gets hurt during them, see a doctor.

A kid rolling on the floor doesn't mean you failed. Their brake is still being built.
What set off your kid's most ridiculous meltdown?
UP NEXT

How Do Babies Learn to Talk?

Babies don't memorize words. They listen, quietly count which sounds stick together, keep the sounds that matter, and learn from real people.

No. 122 · 5 minKeep going →
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