The Human Body (1998) s01e03 Episode Script

First Steps

Childhood - from newborn baby to infant.
From toddler to the first day at school.
To crawl, to walk, to talk, to become an individual, it is four years of miraculous achievement.
Never again will the human body change so fast or learn so much.
This is the story of that remarkable time.
It all begins with the most treacherous journey of our lives, from our mother's womb to the outside world.
As recently as Victorian times, one in 20 babies died during birth.
Death affected everybody, including royalty.
Here in Windsor Castle is a memorial to Princess Charlotte and her son.
Just one year after her marriage in 1816, she was expecting a baby.
Tragically, the birth was a disaster.
The baby boy became stuck inside his mother.
After two days and two nights of labour, the unborn prince was dead, and a few hours later, Charlotte died as well.
Their deaths meant the crown eventually passed to Queen Victoria, and the rest is history.
With modern medicine, Princess Charlotte almost certainly would have survived, and her little boy would have become king.
Today in Britain, very few babies will die.
But that journey, just ten centimetres in length, remains as fraught with danger as ever.
(HEART BEATING) (W0MAN) Go on, Jane.
For nine months, the baby's been fully equipped for life in the warm liquid world of the womb, relying on its mother for food and oxygen.
It's in for a rude shock.
As the baby is squeezed down the birth canal, dramatic changes have to happen.
The key to success is the trauma of the birth itself.
It's so severe, the baby has adrenalin levels even higher than that of a person suffering a heart attack.
This rush of adrenalin will kick-start the baby's breathing.
(W0MAN) Well done, that's brilliant.
Here he comes.
Yet even now during birth, the baby's windpipe and lungs are still full of liquid from the womb.
If they aren't quickly emptied, it will drown.
The fluid drains away as it's absorbed into the lung walls.
Air rushes in.
Life-giving oxygen can enter the blood vessels of the lungs.
The first breath triggers further upheavals inside the tiny body.
(W0MAN) That's it, Jane.
Well done, sweetheart.
Well done.
(MAN) Excellent! Well done! (W0MAN) Well done.
Remarkably, even at this late stage, the heart of the baby is not yet ready for life outside the womb.
In one of the interior walls of the heart there is a hole.
This opening was vital when the baby had to pump blood to the placenta.
Now it's a liability.
Blood flowing through a newly-opened vessel will slam shut a flap of tissue to seal the vulnerable hole.
It forms a solid wall, and the four chambers of the heart are finally complete.
In an adult, such major changes would require open-heart surgery, but here they are happening instantaneously and unseen inside the baby.
This is the miracle of birth.
(W0MAN) Now we'll cut his cord.
Can Richard cut the cord? It's a boy - Bob.
The umbilical cord, the last link to his mother, is cut.
Bob's first challenge is to keep warm.
A heat-sensitive camera reveals the coldest parts as blue.
Bob's toes and nose suffer most.
The delivery room is 15 degrees colder than his mother's womb.
(W0MAN) He looks fine.
Yes! A special type of fat is concentrated on his back and around his chest.
This baby fat can be broken down to release emergency heat.
But for the first six months of life, Bob's ability to control his temperature is very limited.
For the moment, he relies on blankets and cuddles.
(MAN) He's shivering a bit.
(W0MAN) You see his little lips going.
(M0THER) He's cold.
A little bit cold.
He looksdark hair, yeah.
(W0MAN) Those little marks will be gone by tomorrow.
(MAN) It'll take no time at all.
(W0MAN) It was all a bit of a push.
Bob's tight squeeze through the birth canal has left his head an odd, pointed shape.
His skull is so pliable because the 22 different bones that make it up haven't yet fused together, leaving holes between the bone plates.
Bob would never have made it out of the womb if his skull hadn't evolved to be this way.
From now on Bob will live under the watchful eye of his proud parents, Jane and Richard Jeffers.
His hazardous journey into the world is over.
- Thanks, Richard.
That's brilliant.
- There we are.
Just pop him down here.
(JANE) It's just amazing to see that he's perfectly formed in absolutely every way, his arms, his legs.
He's got quite a tidy little nose.
He's got a nice mouth.
He's got quite a wide mouth.
Everything is just perfect.
It's just a miracle.
You don't see that they're wrinkled up and all those other things.
His face looks really quite well established for a small baby.
He's got a lot of character.
In a strange sort of way, he looks like a little old man.
Although Bob is helpless, he has a fantastic survival strategy.
Parents find their new baby irresistible.
(JANE) Oh, Bob.
Is that nappy bothering you? They do control you to a point.
Their demands are paramount.
If they cry and want feeding, you've got to do that.
If they need changing You can't ignore their needs, because they're dependant on you.
This is the best bit, isn't it? A bit of fresh air to that bottom.
It's almost as if Bob has put his parents under a spell.
You're just too good to be true Can't take my eyes off of you You'll be like heaven to touch And I want to hold you so much At long last love has arrived (RICHARD) Bob'sfirstpicture.
You're just too good to be true Can't take my eyes off of you 0ver a period of six months, we followed Bob's rapid development.
Just a few weeks after birth he was a bundle of reflexes, a handy set of automatic responses that help him survive.
Can he hear you? Yes, he's startled by loud noises, and he can definitely hear me.
A young baby will try to grip with his hands anything he touches.
Young apes grasp on to their mother's fur.
But even in hairless humans this grasping reflex can be useful for holding on.
I'm just going to check his reflexes.
A reflex is activated by any touch to the palm.
Here, the baby's hand has grasped a finger.
Inside the hand, you can see the muscles that even just after birth can support the weight of the baby.
Ironically, the hardest thing for babies to learn is to let go.
Their fingers have to be prised open.
And Bob's toes will try to grip as well, a throwback to our ape-like ancestors who held on to things with their feet.
These reflexes are completely involuntary.
They require no more conscious control than the contraction of the eye's pupil to light.
Are you ready? Ready for your milk? Another reflex helps Bob find food.
Although he doesn't know where food comes from, whenever something brushes his cheek he automatically turns his head from side to side and parts his lips.
This is the rooting reflex.
He just finds it himself.
He'll find it.
You just need to put his head somewhere remotely near, and he's there.
And that's not all.
The milk that's produced in the mother's breast can be activated merely by the sound of the baby crying.
That's a lovely boy.
Bob not only manipulates his mother's behaviour but also her body.
What a face.
Got a full tummy there.
Newborn babies have another reflex which is much more mysterious.
In fact, it's an ability so odd that until recently we didn't even realise it existed.
Actually, it's a reflex we all had in the first six months of life.
Watch this.
It's called the diving reflex, because it stops the baby from breathing under water.
Wow.
She's more comfortable than I am, I think.
The mouth can be wide open, but inside the baby the top of her lungs is sealed off, and any water is diverted down the oesophagus into the stomach.
Perhaps more amazing are the baby's movements.
Not only do the arms and legs move in a coordinated stroke, but the torso flexes enough to propel him through the water for over a metre.
However, after a few seconds they all need adult help to regain the surface and the vital next breath.
Hey, up you go.
Some people believe these abilities come from a long-lost ancestor who spent most of its time in the sea.
0thers think it is a hangover from our life in the liquid-filled womb.
The truth is we don't even understand the origins of this remarkable ability.
For the moment at least, it remains a delightful mystery.
As the baby's mind matures, these involuntary reflexes are suppressed by conscious thoughts and movements.
This has already happened with Max, Bob's three-year-old brother.
The reflexes are no longer needed, so they eventually disappear.
In the buzzing, booming world, both reflexes and conscious thoughts depend on the senses.
But at first Bob can see little.
Contrast is poor.
Anything beyond half a metre is out of focus and blurred, and he may even see double.
0ne of the reasons Bob is so bad at focusing is hidden inside the eyes.
A very young baby does not have proper control of the muscles that change the shape of the lens.
The lens, here coloured white, is fixed at one set shape.
To focus on objects far away, the tiny muscles around the lens need to stretch it into a thinner shape.
It'll be a while before Bob learns to do this.
Are you gonna try? Yes! Clever boy! By two months, his vision will have improved.
He seems to like looking at faces best, and it's at this time he will first smile, a magic moment for any parent.
He still was only about three weeks.
Then I realised that he was actually smiling back at me.
Smiling and recognising a smile are crucial milestones.
So a team in London are finding out what's going on inside the head of this baby girl to see how she does it.
You're a very good baby.
Very smiley.
They measure the electrical activity in the brain when she looks at different faces.
A scowling face.
A smiling face.
And an upside-down face.
The patterns of brain waves prove that the baby first sees it as a face, right way up or not.
And then, a fraction of a second later, she checks out what emotion is showing.
And these two tasks actually happen in different parts of the brain.
You might assume a baby's brain is just the same as an adult's, only smaller.
But it's not.
A baby's brain is nowhere near finished.
New connections between the hundred billion brain cells are being made all the time.
Throughout babyhood, the brain is sculpted.
So our experiences in our first few years will determine the brain we have as adults.
This developing brain is so demanding that over half of all the food Bob eats goes to driving it.
To supply this much energy, it is essential that he moves on from milk.
To deal with solid food, things are stirring underneath his gums.
His first teeth will grow up from tiny tooth buds that have been hidden in his jaw since long before he was born.
But they won't start to burst through his gums until he's around six months old.
For the first time, over 40 days, this dramatic event has been filmed.
No wonder babies cry when their teeth come through.
At birth, Bob was a tiny bundle of reflexes and flailing limbs.
0ver the following six months, he has grown quicker than he ever will again.
He has more than doubled in size.
But he hasn't just been putting on weight.
What is less obvious is that his mind has matured.
For the first time, he can control his hands and reach out to grab objects.
He is turning his desires into actions, a sign of his burgeoning personality.
A baby at this age is soon ready for the next key advance: mobility.
0ne stage ahead of Bob is Zak Troullous.
Zak is already seven months old and lives in London.
0ver the next few months, he'll take his first steps and speak his first words.
But for now that's all in the future.
He seems to be developing very normally.
And that's great.
Has he tried to pull himself to stand or anything like that? When he's sitting down, he goes forward or falls on his face.
So he's a bit scared.
Right, it's a good time now while he's sitting to think about making sure that the environment is safe for him.
Because everything tends to go straight from hand to mouth.
He's trying to chew his shoe.
Zak's mouth is the most sensitive part of his body.
The tongue is teaming with nerve endings.
That's why babies are so keen to use their mouths to explore the world.
But Zak's scope for exploration is limited.
He still relies on his parents to get around.
Things will have to change.
We normally associate crawling with reptiles.
Think of the sprawling waddle of a lizard.
But it's actually a powerful way of getting around.
All movement of the human body is surprisingly complicated and difficult to analyse.
But in order to understand motion, analysis is what you need.
That's what these little markers are all about.
They can be tracked on a computer to reveal the underlying motion of my skeleton.
It's the only way you can follow something even as seemingly simple as the movement of a limb.
Dozens of joints and bones moving in harmony.
Even a clapping stick man is characteristically human.
This baby is doing the diagonal crawl, moving opposite limbs together, right arm, left leg, then left arm, right leg.
The arms absorb the shock of impact, while the power is provided by the legs.
The top speed of a crawling baby is about two kilometres an hour, and the average baby crawls perhaps 200 metres a day.
If you look carefully, motion capture can identify seven different types of crawling.
The elephant crawl is where just one limb is moved at a time.
But the diagonal crawl is the most popular.
It's extremely efficient, combining stability with speed.
This crawl takes a while to perfect, as Zak is finding out.
(W0MAN) He's crawling slowly.
(MAN) But he's still got that wobble.
- As each day goes by, he gets better.
- Bad coordination.
Once he gets that (W0MAN) He needs a bit more confidence.
Before I put him down, I gather a few toys, and I go into the kitchen for a few minutes.
I know he won't move.
But now, because he's crawling, he's going to the stairs.
You've got to keep an eye on him every second of the day.
Until he started crawling, Zak had no fear of heights.
Now he is increasingly wary.
We're gonna put your weights on.
At a university in America, Karen Adolph experiments with crawling babies to discover how they deal with treacherous slopes.
As a further challenge, the babies are weighed down with two kilograms of lead.
They then meet the apparatus.
Mother tempts her daughter from the other end of the ramp.
Come on, Natalie! 0nce she's scoped her target, the baby visually assesses the slope.
She confirms the severity of it with careful touches of her hands.
Karen has discovered that they can gauge the angle of a safe slope to within just two degrees, a tiny fraction of the slope overall.
If they decide it's a bit too steep, they'll adjust their crawl, maybe even coming down backwards.
Crawling is not just about how to crawl, but what's sensible to crawl down.
If it's way too steep, the baby will wisely avoid the drop altogether.
However, the real revolution in getting around is still to come.
Zak, are you gonna walk over to Daddy? Are you gonna make it? Zak is 11 months old.
He's about to express what human beings have felt throughout 3,500,000 years of evolution: an overwhelming desire to rise up on two feet and free the hands.
Can you walk to Daddy? Zak already has the strength to stand up with a bit of support.
But his ability to walk comes not just from his legs, but also from deep inside his ear of all places.
At the end of the ear canal are the bones we use for hearing.
Behind these is the balance organ.
The balance organ is a miracle of engineering, made up of three circular tubes full of liquid.
Anchored to the inside walls of these tubes are tiny hairs.
As Zak moves, the hairs also move, telling him the position of his head.
The three tubes each have their own orientation, which detect the three basic types of movement in space: roll, pitch and yaw.
This device will allow him to take his first independent steps.
(MUSIC: ''WALK LIKE A MAN'') Walk, walk, walk, walk Walk like a man When he realises he's let go of something and he's standing on his own two feet, he realises what he's doing.
He gets scared.
He loses his balance completely.
But he tries.
He's a hard trier, keeps going for it.
It's been a long 12 months for Zak.
Learning to crawl and then get up on two feet have been key achievements.
Zak can now walk tall on his own.
Happy birthday to you Happy birthday to you Zak is a new-experience junkie.
As eating is food for physical growth, so experience is food for brain development.
(MAN) Oh, where's it gone? It's gone! Zak may be walking, but he faces another barrier to further progress.
Imagine what it's like for an infant to understand so very little of what's going on around it .
.
to feel lost and excluded from the social world.
The closest we get to it is a holiday abroad.
- These are too old.
I want something new.
- (IN ARABIC) Trouble is you can only get so far with mime and pointing.
Can you take me to the pyramids, where the kings are buried? As a child, one thing you lack is an accurate way of explaining your desires, exactly what you feel, what you really want, or any way, really, of telling your parents what to get for you.
What you need, of course, are words.
Every human culture has depended on them, be they spoken or written, like these hieroglyphics.
Words and language are the most important thing a child will ever learn.
Not just words to describe things you can point at, like sand or rock, but words to describe abstract things: your past, your future, your fears, your hopes; words to describe discoveries and ideas, to communicate them to other people down the generations, ever expanding the wealth of human knowledge and experience.
The whole world we have built is built upon language, and yet it all begins so simply.
Mama.
It seems a miracle, but 15-month-old Zak can begin to master the complex power of language, an infinitely flexible symbolic system, and yet still needs nappies.
Bravo! (IN GREEK) Even more impressively, Zak is learning English and his parents' other language, Greek.
When babies first learn to speak, they use a completely different part of the brain from adults trying to learn a foreign language.
That's why it's so natural for babies and such an effort for adults.
(IN GREEK) But it's not just Zak's brain that gives him his power.
A newborn baby has a vocal tract just like any other animal.
The larynx, a pipe at the top of the lungs, is positioned high up, right at the back of the throat.
It sticks up like a snorkel above the flow of milk to the stomach.
This ingenious arrangement allows the baby to breathe and suckle at the same time.
But with the larynx so high it can't perform its major function in life - speech.
By the time Zak is a year old, the larynx needs to have dropped a whole three centimetres lower.
Where's Mummy? The lowered larynx now lives up to its other name, the voice box.
With more space at the back of the throat, the voice box can make an extraordinary variety of sounds.
As air passes through the gap between the vocal chords, it causes them to vibrate.
The tighter the chords are, the higher the pitch.
And the final sounds are shaped by subtle movements of the tongue.
To create just one recognisable word, Zak has to coordinate over 30 different muscles.
Mummy, Mummy! - Daddy! - Yeah, you're in the water.
Cold.
Unfortunately, this lowered voice box makes humans especially vulnerable to choking on food.
As a species, however, this occasional problem is outweighed by the power of language.
The human larynx has evolved so that the way it changes suits each stage in life.
Zak can finally communicate.
- (IN GREEK) - Mummy, vroom vroom.
We'll go later on the vroom vroom.
Later.
- Uh-oh.
- Uh-oh.
0ver the previous year, Zak has progressed from baby to toddler.
But the pace of change does not let up.
Look ahead another year and the child will have raced ahead again.
Boom, boom.
My name is Moira.
Oh, lovely! Look at that! We're good at this! High five to both of us.
Yeah! Now I know my ABC This little girl is two-and-a-half years old.
Moira lives in a peaceful suburb in New Jersey.
I'm gonna go water.
Like all toddlers, she's learning a staggering ten new words a day.
It did seem quite quick that she was able to communicate or to describe things in detail.
It seemed really fast.
Uhmthank you.
At one point, you think she's able to just sort of react with words, and then it's amazing when she's able to take words and think about the future and what could be possible.
You know what this is over here? What do you think it is? (B0Y) Turkey.
(W0MAN) Very good.
You like turkeys? - Can you make the noise? - Gobble, gobble.
- Gobble - Gobble Moira has never seen a baby deer before and doesn't know the word for it.
This is the first time she will ever say it.
(W0MAN) Do you know what to call one of these things? Well, some people call them Bambi, but that's after the movie.
They're called a fawn.
- Can you say that word? - Fawn.
Not only is Moira an enormous sponge soaking up new words, she knows automatically how to construct them into proper sentences.
Children have an instinctive knack for language and get the grammar right virtually all the time.
But their occasional mistakes are telling.
It's almost always when the grammar is irregular.
What if I had one mouse and I had another mouse, I'd have two what? - Two mouses.
- Two mouses? There's another word for plural for mouse.
What is it? Do you remember? It'd be two? - Mi - Mice.
Two mice, that's right.
Very good.
Good job.
Moira created the word ''mouses'' herself by just adding an S.
It's impossible for her to have imitated the word from an adult, because they never use it.
Instead she applied the logical rule for making a plural and has to be taught the exception.
So why is it that toddlers can learn language so rapidly? The theory is that throughout evolution little children have always faced grave dangers.
The quicker they learnt language, and the better they understood the warnings, the more likely they were to survive.
In just the same way that a clam has evolved a tough shell to protect it, we have evolved language as our defence.
(W0MAN) Guys, you need to be careful of the water! Come back up here! But language is not just a simple one-off trick like the clam shell.
Its power and flexibility are unique.
It's given rise to our rich social world, delivering us a decisive advantage over other animals.
Alongside language, children learn another skill, a skill adults rarely give much thought to.
You and I know that this is me, but we also know that this is me, too.
It's so simple it sounds silly.
But, in fact, though we take our ability to understand mirrors completely for granted, we're one of very few animal species that has the slightest idea what's going on with them.
A monkey can't recognise itself in a mirror.
But a chimp can.
Interestingly, it's a skill humans are not born with.
14-month-old Julia ignores the red dye painted on her nose.
She fails to recognise the reflection is her, because she doesn't yet have a proper sense of herself.
Julia lacks self-awareness.
Unlike Moira, who's over a year older.
Yeah! Look at those pretty things! Moira also uses words like ''I'', ''me'', ''mine'', proving she is now aware she is a separate person from everyone else.
Got you.
- Who's that? - You and me.
- You? - And you.
- And me? - Yes.
Unfortunately, there's a dark side to self-awareness, too.
- Liam, I want Sharky! - Liam, bring the shark back, please.
- Liam, bring the shark back, please.
- I want Sharky! - I want Sharky! - Look, the shark's going through the sand.
Thank you.
Moira sometimes uses tantrums to get her way.
This is the Terrible Twos, when she has the self-awareness to recognise her needs and the language to express them all too clearly.
All the changes in Moira's view of the world are taking place because of alterations inside her maturing brain.
Different skills, such as language and self-awareness, are clamouring for space in particular parts of the brain.
But there's still something missing.
It's a series of developments that will take two years to perfect, and it's all about getting on with other people.
James is an active four-year-old who lives near Philadelphia.
But he's unusual in that he has two brothers exactly the same age, Sean and Evan.
(B0Y) I will give it back.
(W0MAN) James.
We call him our athlete.
He's very athletic and pretty strong.
Sort of acts like the older brother, because he is so much more advanced.
- Wow! - A big one.
Look at that bubble Evan has! Evan is different.
He's very moody.
We call him our moody artist type.
Sean is the smallest of the three.
And because of that, he learns to compensate a little bit.
And so we call him our politician, because he's used to trying to negotiate for things and is a little more tolerant of things in general.
Part of getting on with one another and dealing with the social world is learning and complying with rules.
We got a set of rules based on their interaction.
Mostly like, you know, no-fighting rules, no playing on the stairs.
(W0MAN) No hitting, pulling hair.
No hitting, no fighting, no biting, no scratching.
No throwing, no throwing suitcases, no throwing bottles, no throwing houses.
If somebody does get out of hand they do end up in their room by themselves for some quiet sort of time-out-themselves time.
James! Are you supposed to be taking those cookies now? - Mom, just a little.
- No, that's not OK.
Are those cookies for now? No, those are special cookies.
Those are for later.
No, that's not OK.
Now put the cookies back.
Breaking the rules leads to shame.
Look at the classic hunched shoulders and the drooped head.
James knows he's done wrong.
He's starting to acquire a conscience.
But no sooner are children taught the rules than they discover a way to get around them.
Lying starts surprisingly early.
But until recently it's been considered well nigh impossible to study.
Child psychologist Michael Lewis has created an ingenious test to reveal more about lying.
He and the mother of the child he's studying hide behind a one-way mirror.
I have a toy under here.
I'm gonna uncover it, but don't look.
I want you to keep looking straight ahead.
Don't turn around, don't peek.
I'm gonna uncover it and turn it on, but don't look.
I have to get something I left in the hall, so I'll be back in a minute.
But don't look at the toy while I'm gone.
Keep looking straight ahead.
When I come back we can play with it, but don't look at it, OK? Don't peek.
So, what do you think he's gonna do? - I think he'll lie.
I think he'll look.
- He'll look and lie.
OK.
Let's look and see.
He's holding out.
He's holding out.
His eyes are starting to He's gonna peek.
OK.
You know, I have to tell you that three-year-old children, about 70 percent of them peek.
And when they peek, almost all of them lie.
Jerry, did you peek? No? Good for you.
You wanna turn around and play? All right, go ahead and play.
Well, you were right.
They peek and then they lie about peeking.
And they lie because they don't want to get into trouble.
And if you think about it, it makes sense.
Not only didn't they do something right, but they may get punished for it.
And so it turns out that the smartest kids are not the ones who tell the truth, but, in fact, the ones who lie about it.
And it's true.
At this age, the higher your IQ, the more likely you are to lie.
To lie deliberately, these children have to be aware that the experimenter doesn't know whether or not they've peeked.
- Did you peek at it behind you? - No.
This awareness that other people can have different beliefs and thoughts from your own is not just useful for the occasional fib.
It's a crucial stage.
All children need to pass it before they are ready for the adult world.
Scientists call it ''theory of mind''.
But it's not as difficult as it sounds.
It's our human skill of working out what another person might be thinking.
To do it, we need to realise that each of us has different wishes and intentions, likes and dislikes.
My thoughts and desires are not necessarily the same as yours.
We do it all the time without even being aware of it.
Yet theory of mind is the very cornerstone of all our relationships with other people.
But at three years old these children are too young to have learnt it.
Jack and Jill went up a hill The triplets are just four, and HAVE developed theory of mind.
Take hide-and-seek.
If you think about it, it's quite a sophisticated game.
The boys know their dad won't be able to see them if they hide themselves properly.
Roar, roar! Sweet, look at the hiding guys.
They realise his view of the world can be different from their own.
I see a hip-hop.
There is the James-boy.
Theory of mind is even more essential in making sense of stories.
To follow what's going on in Snow White, the triplets need to grasp that different people will see the world differently.
Most children younger than three will assume Snow White has the same knowledge they do: that the apple is poisoned and Snow White shouldn't eat it.
This makes a nonsense of the story.
The triplets, though, know better.
- What was the old woman giving her? - An apple.
- But what was it really? - A poisoned apple.
- But what did Snow White think it was? - A present.
A present.
Who was that? A mean queen.
- And what was she trying to do? - Hurt Snow White.
Was it a nice thing to do? It was a BAD thing to do.
Understanding what motivates others, in fairy tales or real life, seems obvious to us.
But it's a key turning point in every child's development.
By scanning people's brain activity, it's been possible to identify the part of the brain where theory of mind develops.
Tell stories that require it, and this important section right at the front of the brain literally lights up.
In the triplets, the brain connections of this area are now almost complete.
Theory of mind is the final piece of the jigsaw.
It marks the transition from babyhood to childhood.
0nce a child has made it, the world will never seem the same again.
La cucaracha, la cucaracha La, la, la, la, la, la (W0MAN) We'll miss them when they go off to school, because pretty much all of our time and energy goes into managing them.
This is our favourite song again.
Can you guys sing along to the song? We have mixed feelings.
It would be great to have some time, but then it'll be scary to send them out into the world, just to be so independent.
Do you have your backpacks ready? La, la, la, la, la, la, la 0le OK, hold on.
And you're next, big guy.
- Have a good day, OK? - Bye.
I wanna see you climb those big steps.
Yeah.
Hold on to the railing, and have a good day at school.
0ver just four years the triplets have met all the challenges this new and exciting world has thrown at them: to walk, to talk, to understand the thoughts of others.
They are ready for the next stage of their lives.

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