All language subtitles for Babies.S01E03.NF.WEBRip

What's that?

That's a dog.

Yeah.

That's a dog.

Can you come to the dog?
Look, it's a doggy.

It's nice. Nice dog.

For the first
several months of life,

infants are slaves to gravity.

They're just stuck in whatever place
somebody put them in.

And then this remarkable
transformation happens

when babies learn to crawl.

Wee!

Now they can move their own body
from one place to another,

and now the whole wider world
is opened up to them.

Hey, bubba. Hi!

Hey!

Hey!

But how is it that babies learn to crawl,

and what do they learn

when they're crawling around in the world?

You can do it.

In the first year of life,

babies are growing faster
than they ever will.

Come on, you can do it!

The baby can wake up
in a different body

than they went to sleep in.

It's longer.
The arms are longer, the legs are longer,

and as they begin to move, they cannot do

exactly what they could do yesterday

with the same precision.

You can! Call him here!

What does this mean for a baby
who's learning to crawl?

For decades,

we really believed that crawling
was just a stage toward walking,

but could crawling be more than a stage?

Could crawling be fundamental

to the way we all move?

Ready?

Who is that?

Take a video for Mum.

Now that Amelia's back at work,

I kick into my primary carer role
in earnest.

Look, who is that? Who's that?

Is that Pascoe?

There's Dad, there's Pascoe.

Which I'm really excited about,

just because it's great time
I get to spend with Pascoe.

And we're gonna get back
to practicing some tummy time,

see how he's doing with crawling.

Ready? Who's this here?

When Rich starts telling me,
"Oh, we did this today,"

and, "Oh, Pascoe started crawling today,"

or "He did this move..."

Get your arms going. That's it. That's it.

Who's there?

And I'm sort of sat at work,
just at my laptop...

Good boy.

You know, I feel like I'm missing out
on quite a bit.

Good!

Oh.

Hey!

I think also as a first-time mum
you're quite keen to sort of

tick off all the milestones,
and you sort of read the books

that say, "At this stage
your baby will be doing this,"

and you're like,
"My baby's not doing that,"

or "My baby did that two months ago.
Is he too early?"

Good, he's got it!

First past the post.

Oh, and you even pressed stop
on the video. Good boy.

You know how it works.

You know how it works.

You know how it works.

My career is not a straightforward,
I would say, uh, trail.

Not at all.

I started to be
a nuclear physicist.

I was studying the movement
of electrons and atoms.

And then, as a biologist,

I switched to be more interested
with the movement of the body.

All of the steps gave me an open mind...

to different ideas
that you can have about movement.

Many people thought for a long time

that crawling emerged only around eight,
ten months,

and is a transitory step toward walking.

However, it is maybe
more mysterious.

I think for me the question was,
"Could crawling be more than a stage?

Could crawling be crucial to the way

all humans move around?"

What can I get for you?

I'll have a coffee.

- That's alright.
- Thank you.

In the womb,
fetuses are able to move

from one place to another place
if they want,

and you have to imagine a newborn
as an astronaut

coming back from the moon,

where it was able to do
a lot of movements freely

and now is stuck with the gravity.

But there are specific times or occasions

where you can see a newborn moving
his body from one place to another.

Around one hour after birth,

if the baby is skin to skin
on the belly of the mother,

you will see the newborn moving slowly
to the breast of the mother.

And this is a fantastic behavior.

I love it, I saw it a lot.
Many, many times.

So another occasion
is to put the newborn in the water.

The first time that I saw that,
I was just, uh, shocked.

I said, "My God,

these newborns are able to do
a lot of things,

and they are already able literally
to crawl in the water."

And so it is where I get
very interested with this movement,

and starting to ask,

"Is this crawling that is already here

really disappear to reemerge
eight or ten months later

for the baby to learn
how to do that on land,

or is there a link
between these two behaviors,

the newborn and the older baby?"

People believe
that newborn movements

are only reflexes that will disappear
very soon after birth.

And so they have nothing to do

with a connection coming
from the brain to control the movement.

But with that newborn,
crawling was so beautiful,

it's not really an automatic system.

It could not be.

This is why we thought
of a very crazy experiment.

So the question we asked
was relatively simple...

Was the crawling
that we saw in the newborn

already controlled
with something in the brain?

And one of the stimuluses of the brain,
one of the most important systems

that controls the crawling at seven,
eight months,

is the vision.

Hello, have you had
a good journey?

Yes, very good.

Look how he's grown!

So knowing the importance of vision,

we were wondering,
and this was really our big question,

what will happen to a newborn

if we give them the illusion

that they are moving around?

Voilà.

Will they move? Will they not move?

Let's not forget his little hat.

The hat of an astronaut.

Hop là.

There you go.
Ready to go to space.

Exactly.
We're going to send him into space.

What we have done
is to imagine black dots

that are moving on a pattern
that is completely white.

So to get the impression of moving,

you have to have all the dots moving,

and in the same direction.

As soon as they see,

they move their legs and their arms,
and literally swimming.

Swimming in the air.

We were just shocked when we saw that.

We had this idea,

but we were not completely sure
that we will get this, you know, result.

We were very surprised.

Hello, little girl.

Hop là.

Hop là.

This, for us,
was really something incredible

because that means
that they have this primitive link

between the brain and the spine,

and the vision,
and the motoring activity to say,

"Hello, I see something
and I am moving according to what I see."

And this was, for us,
really the first evidence

that this crawling pattern
that you see at birth

is coming from the brain.

What we have here is
an extension of the leg at the same time

as movement of the elbow and arm.

Now, having seen this baby

just swimming
literally in air with arms and legs,

this definitely shows

that this crawling pattern that
a lot of people believe was just a reflex

is not a reflex.

It's wonderful.

Let's take your hat off for a minute.

Voilà.

Look at Mom and Dad.

We started to think of how to study
and analyze the same kind of movement...

if we put them on land.

We knew thatit's very
difficult for babies to propel themselves,

because the head is very heavy,
it's one third of the weight of the body.

So they are not able
to support that in the gravity.

Oh!

- Can I come in?
- Yes.

- Hello.
- Hello.

Ah!

So, Hello little Helmi...

So now we start
about thinking

how to make the baby free to move around,

and how to find a tool finally

for them to be not crushed

by the gravity and having their arms
and legs free to move.

Would you like to participate
in this experiment

which will last around ten minutes

and a little longer
to get Helmi downstairs?

Let's go.

So we were thinking a lot

about how to construct such a tool.

We thought it will be easy to do it.

But not at all.
It took us, like, one or two years

to build this kind of tool.

- Hello.
- Hello.

So we started to test our first baby

on this mini skateboard in 2016,

and, uh, we call the final version

"the Crawlerskate."

He's looking now.

They are comfortable,
that sometimes triggers it.

They do whatever they want.

We explain
what is the Crawlerskate,

and all the time they are very interested

because they think
their newborn cannot at all crawl.

Hop, hop, hop!

Ah.

Some babies are making a huge movement,
even crossed the mattress

once or two or three times.

It seemed really incredible.

Wow!

Bravo! Bravo!

Bravo, Helmi.

We were just shocked to see

that these little two days newborn babies

were able to do that on our Crawlerskate.

I find it emotional
every time they move like that. Huh?

Too good.

It was really
a very emotional moment, I can tell you.

Not only for us, but for the parents.

Hop là.

If we look at the results
that we obtained with the Crawlerskate,

what that suggests
is that the nervous system

that is important for the baby to move
their arms and legs

and crawl

and to propel themselves

is already in place.

- Thank you very much. Goodbye.
- See you later. Goodbye.

So what we have found

is very new,

and controversial.

Because for decades,

people believed
that we were born as bipeds.

That means that we are walking
only with our two legs.

But what we have found
is a completely different picture.

We believe now that we are born

moving arms and legs...

as quadrupeds.

If you look at adult walking,

it seems to be automatic
to move our arms when we are walking.

But in fact we can do much more than that.

We are still quadrupeds
inside us,

in the nervous system.

So is crawling

just a transitory stage?

I think now, no.

Wake up now.

We need you today.

In fact, if you see the baby as a car,

the engine is, like, sleeping and waiting

for the bodywork to be ready,

for the moment where the baby will be
strong enough, with strong muscles,

to take care of the weight

and to be motivated to move it.

For that, the baby will have to grow.

And this is another story
of how the baby grows up...

Hey!

...and changes the body
with maturation and experience.

Mwah!

Hey!

What a yawn!

Good boy.

All right, should we see
if he can do the crawl?

Come on. Oh.

A bit of a... A bit of a bump.

Oh, there's a push. There's a push.

Use those legs.

Come on. Good boy.

Good boy.

Oh, oh...

That's it.

You little champion!

Push up.

Good boy.

Oh, hello.

Very good.

Good boy.

Lift yourself up.

Wahey! Look at that!

Right, just...

getting a bit happier staying
on his front.

There, you've got that the play with.

Pascoe does seem
a little bit unsettled during the day.

Probably he's just going through
a bit of a growth spurt,

or a developmental spurt.

He seems to just be getting
longer and longer,

and stronger and stronger.

You can do it.

That's it.

He's got the legs going.
The legs are pumping.

He's getting bigger,
that's for sure.

He's got some good power in his legs

and I think he's starting to feel
that in his feet.

Okay.

- Good work, buddy.
- See?

I think we thought
that he would be crawling by now, so...

You can start crawling if you'd like.

Would you like to start crawling?

I started out in anthropology

with an interest in the interaction
that babies had with their families.

Every parent experiences

how disruptive

babies can be.

They're sleeping, and then there's no way
they will go to sleep.

There are times
when they're not very hungry,

and times when they become very hungry.

Or out of nowhere
they become kind of morphed,

and parents will say,

"Who's this monster who yesterday
was such a good little girl?"

It occurred to me that knowing
something about growing

would be informative here.

In 1979, my neighbor
was about to have a baby,

and I suggested to her at some point,

would you mind if we measured your baby?

She was very kind and she said,
"Yes, of course."

- Good morning.
- Good morning.

Okay, should be see how long you are?

Measuring a baby's length
is a two-person job.

Are you ready? Set? Measure!

Whoopsie!

You have somebody
who can focus the attention

of the infant correctly,
and then you need somebody

to actually stretch the baby out.

Good job.

Excellent, Aspen. Thank you so much!

Very good job!

Yeah!

I very clearly remember that I was

a little concerned about doing it,
but we did it.

And I wrote the measurement down,
it was 62.7 centimeters.

The next day I come back...

and we go through the process again,

take the measurement.

It was very different.

Sixty-four point five.

I thought, that can't be,

because yesterday it was 62.7 centimeters,

but today it's 64.5 centimeters.

My first reaction was,
"Well, I'm really terrible at this.

I mean, I'm terrible at this.
Because that's way too much."

I came back several more times.

And each time we measured the baby,

the length of the baby
was 64.5 centimeters.

Now I was actually quite unnerved,

because there was no growth.

I've just taken five measurements,

none of which
are what you would expect to see.

One is too much,
and then there's no growth at all,

and that's not possible.

How much of my data
reflect the fact

that I don't know what I'm doing

because I'm new, and I'm a novice?

And how much of this might be...

um, a moment of...

"Who knew?"

And that's where I began.

Hey, bubba.

Hey, Mateo.

Yeah, you're smiling now.

Your sleep has been more difficult lately,
hasn't it?

And Mama is very tired.

What else is going on with you?

He's going through a growth spurt,

and there have been moments where...

Mateo has just, like, randomly

just burst out into hysterical crying,

and there's been
no particular reason for it.

Yeah, you're lucky you're so cute.

Yeah, you're lucky you're so cute
and that I love you.

'Cause you've been a handful.

Yes, you have.

Yes, you have.

You've been more difficult with your naps.

Yes.

You don't want to sit down for too long.

Yeah, you want to pull yourself up.

Yes, you do.

Oh, don't get upset.

Don't get upset.

Yeah, I know you don't like
to lay down.

Okay, it's okay.

He's definitely taking more attention now.

He wants more attention now.

Which is harder to get things done
in the house.

Mateo.

We used to think
that babies grew every day.

Little by little. Slowly, very slowly.

That it was a kind of
background noise of life.

There's a growth chart
in every pediatrician's office,

so every parent has seen
their child's size

plotted on a growth chart.

These particular charts show
the size of 882 children

that were measured at ages one week,

two weeks, four weeks,
six weeks, eight weeks,

and then monthly thereafter
until one year of age.

When we look at a growth chart,
we see a curve.

But the curves are actually

a result of a connect-the-dots process.

There were no measurements
between these two specific time points.

But it creates the visual image

of how growth occurs.

Very slowly and continuously through time.

Is it actually continuous,

little by little,

every day, as we all assume it is?

I set out to measure 30 babies,

because 30 babies would be
a reasonable scientific size.

Also, when I started measuring babies,

I asked parents to please keep a record

of their baby's behavior

on a day-to-day basis.

These notebooks are the original data.

This was a typical day in my life.

On the 23rd of August in 1981,

I visited 12 children.

And for each of them,

I measured at least

their head and their length.

I met the first family
at 7:20 in the morning,

I remember that quite precisely.

And I saw the last person on this page...

Um, I left their house at 10 p.m.

It looks simple, but that's what it took
to do the measurements.

I noticed that babies
who were measured once a week

did grow in the course of a week.

This led me to wonder,
did it really take a whole week

for that growth to occur?

I decided to measure them twice weekly,

and I noticed that babies grew
in half a week.

And I thought,

does it really take them
one half of a week to grow?

And that moment is when I first started
measuring babies daily.

Scientifically, it was
a remarkable experience,

because I did not know what we would find.

On the 19th of February in 1986...

this child was 59.8 centimeters.

Next day,

the length measurement
for this child was 59.8 centimeters.

The following day,
the child was 59.8 centimeters.

Uh, and one day later,

the child was 60.8 centimeters.

So in this one day,

the child was one centimeter longer.

Among the babies I measured every day,

their growth varied
between one half of a centimeter

and 1.65 centimeters

in one 24-hour period.

In one day,

they grew.

And these growth days were separated
from one another...

in an individual

by two to twenty-eight days of no growth.

And then these bursts,

these spurts,

occurred.

From these records

I was also able to identify a clear link

between the times during which

they were having a growth spurt

and dramatic changes in babies' behavior.

Changes in their sleeping behavior,

tantrums,

and times of insatiable hunger.

Wow.

I was thinking, this is a very big thing.

I was shocked.

I was awed.

I thought this was remarkable,
and it was a moment of...

It was a moment of,
I have no idea how this happens,

but these are the data.

So what we used to think is that growth

happened in a curve.

And what we now can see

is that growth happens in jumps

that separate times of no growth.

Two very distinctive phases.

And the reason that we can see this now

is because of the increased frequency

in the measurements themselves.

The day that the paper
was published

it was on the front page
of The New York Times,

The Washington Post,

and it hit a number of media outlets.

There was a genuine interest.

This is remarkable.

Isn't it exciting that we now
know this about children?

What I did not expect...

was the reaction
from the scientific community.

I was invited to a conference.

And I had a few very nice,

very sensible questions.

And then...

a leading figure in the field stood up

and started by mocking the data,

that this can't be,
we all know this can't be,

because look at the growth curve.

That this wasn't credible,

that it stretched their imagination,

that babies could grow so much in one day,

it simply wasn't possible.

I was not prepared

for that level of...

rancor, at all.

Just not at all.

But I think it's an example of

when one has a model in one's mind,

a model of how things work.

This is classic in science,

and somebody comes and says,
"Well, wait a minute.

Let's consider this."

The reaction to that is very frequently
a kind of...

hostile disbelief.

But I think it's absolutely
consistent with...

how science progresses.

Understanding that the baby
is experiencing its own growth...

It's fun for me, too, you know. Yes.

...and that its body is changing,
and it has to adjust

to its own changing body,

and where it is in space
and what it can do,

is a very different way of thinking
about the influences on early development.

What does this mean

for a baby who's learning to crawl?

Ready? One, two, three.

And then they just stand up.

Yeah!

Is that funny?

Hello.

- Hello.
- Hi.

There's Pascoe!

Hello, Paxie.

So we've been doing
loads of tummy time.

- Has he?
- But not showing much signs

of wanting to crawl.

Wow.

Well, the toys he'll grab,

- but he doesn't...
- Yeah.

He'll try and reach for things,

but his feet don't move.

Yeah, he kind of happily
goes on his tummy for a bit,

but then he gets really annoyed.

It's really worth persisting
with that, Mimi, though.

It's terribly important for them to crawl,
and to use all those muscles,

because that's really important
for their future development, you know?

- Get those legs going.
- Yeah.

It's just hard
when he really hates tummy time,

- and is really upset.
- Yeah.

It's hard to keep doing it.

- Do you think you want to crawl, mate?
- Are you listening to that?

Grandma says you have to.

Oh, he shook his head!

- "No! No, I don't want to."
- No?

Cheeky boy.

I can definitely see
where she's coming from with her concerns,

but there's not much you can do
with a baby.

You can try telling him so many times
"You need to crawl before you walk,"

but if that's what he wants to do...

I haven't always been a scientist.

In college I actually studied fine art.

And on the first day of class,
the professor handed me a plant.

And he said, "Draw this."

Every day

he would come with a different plant
and he would tell me...

"You need to really look at it
and understand how it grows."

So now,

all these years later, um,

I feel like I'm essentially doing
the same thing,

only now I'm looking at babies,

and I'm looking at their movements,
so that I can understand

how does behavior grow?

In the real world,

the ground is not perfectly flat
and empty and uniform.

But for the last hundred years,
and even going on now today,

people study infant crawling
by encouraging the babies to crawl

in a straight line over uniform ground.

But that's not how real mobility works.

In the real world,
as babies are crawling around,

they actually have to make decisions,

they have to use perception
to guide their crawling movements.

So, you know, "Should I crawl
over the edge of the bed

or should I stop at the edge?" Um...

And so I wanted to find a way to test

how do babies use perception
to guide their crawling movements?

If a baby really could perceive

what they can do and what they cannot do,

then they should be able to do it
in a totally novel situation,

something that they've
never encountered before.

So I built an adjustable slope apparatus.

So, for this study,
we want to see how babies, um,

know what actions are possible
and what actions are not.

- Mm-hmm.
- So we're going to ask him to crawl

- over this walkway.
- Great.

It's gonna make a noise, Grant.

It can have really small slopes
like this...

- Yep.
- ...or steeper ones like that.

Gotcha.

Good. I love it.

All right, kiddo, let's go.

Grant is about ten months old,

and he's been crawling
for a little over a month.

Come get it!
We've got it all down here!

Come here!

Grant, come get these.

Yeah.

Good job.

Aah! You got it!

We increased the degree of slant
six degrees at a time.

All right, Grant, are you ready?

I've got it on the tower again.

- Come here.
- Go, go, go! Go, go, go!

We're trying to figure out

how precise are the babies' decisions
about what they can and cannot do?

- He couldn't get 'em
- You've got all of 'em down there! Go!

All right, working on that arm.

Here you go!
Come get the blue one!

On a successful trial,

he crawls from top to bottom,
belly off the floor,

and nobody has to touch him.

Go, go, go! Go, go, go!

On an unsuccessful trial,

his arms give out

or he stumbles

or, you know, he's about to do a faceplant
on the surface

and the experimenter has to rescue him.

- Okay, we're waking 'em all up.
- Come here.

You want to put 'em down to sleep?
Wanna put 'em to sleep?

That's good.

Come put 'em down to sleep!
Go to sleep.

All right.

- Good try.
- There you go!

He's making judgments
thatare completely off

from what he really can do.

Then finally we present them
with the largest slope,

which is really a 90-degree drop-off.

Go, go, go!

It's all the way down there,
you gotta go get it.

- You coming?
- He will.

You coming?

All right!

- Good try, man.
- You got 'em!

Grant approached the 90-degree drop-off

the same way as he was approaching
the shallower slopes.

Come over to the edge,
look and see what's at the bottom...

Oh, the pop-up pals!

And then just crawl
right over the edge.

All right!

That's telling us that Grant
is not yet able to distinguish

what he can do and what he cannot do.

It's absolutely typical that babies,
when they first begin crawling,

when they first begin any new skill,

they just are willing to try everything.

And it's actually a pretty good way
for development to work.

If you don't try things,
you're never gonna learn.

And so they just take the leap.

Go, go, go!

- Go, go, go!
- Yeah.

Marlow's interesting because she's quite
a strong hands-and-knees crawler.

Down you come! Down you come!
Down you come!

Good crawling, Marlow.

In terms of having alternative ways
of coping with a difficult motor problem,

she was, like, right on the edge
of understanding

that, you know, there was other positions

that are available to her
to solve the problem.

Come here.

You can do it.

Babies show really
different kinds of behaviors

as they're approaching
the brink of an impossibly steep slope.

Come on down.

I know, it's so funny. Just come on down.

So I'm pretty sure you can figure it out.

The babies who make
smart decisions,

those are the same babies
that will generate perceptual information

by looking and by touching.

You see that? You coming?

Marlow was quite good at perceiving
what she could and could not do.

She knew if the steps were very steep

that they were impossible.

Xylophone, and...

Yeah!

Wee!

Okay.

Good... Good try, man.

All right.

- I'm gonna send this down to Justine.
- Can I have that?

I'll hold it for you.

Dax would switch freely
between crawling on hands and knees

and crawling on hands and feet
like a bear.

A little more challenging.

He actually can move faster
when he's up on hands and feet,

and so when he really wanted to get
to something,

he would just extend his legs

and, you know, crawl down the pathway
on hands and feet.

He's crawling. What's that?

He was just, you know,
reconfiguring his body on the fly

to kind of figure out
how to solve that problem.

- Let's do it again.
- Perfect.

All right. Are we coming down?

Ready?

We built this tall tower for you.

Dax really, really could perceive
the limits of his own abilities.

Wow!

You did it!

So as the slope started to get too steep
for him to crawl safely,

that's when he was beginning to switch
to find alternative strategies.

Ready?

Come get some down here.

Yeah, they're all waiting for you.

Wow!

Smart thinking.

You got it.

It takes about 20 weeks
of crawling experience

before a baby
is showing adult-like accuracy

when they're looking at
an impossibly steep slope.

What is it
that babies are learning

over all those weeks of crawling?

Definitely not in Manhattan.

Good job.

Good job.

They're learning how to figure out,

in this moment right now,
what is my body like?

What is the environment like?

And what can I do with this body
in this environment?

And those things
will change from day to day,

because they can wake up

and find that they've grown
another two centimeters.

Their mom could dress them
in a different outfit

that is functionally changing
their body dimensions,

or the way that they can move.

Go, go, go! Go, go!

And it's good for your baby
to crawl on grass

or crawl on sand or crawl on whatever,

because learning to crawl isn't learning
some specific pattern of coordination

between your arms and legs,

it's learning to behave
in a really flexible way

so that the baby can get around
in the world.

It's tummy time again?

Huh?

What do you do in tummy time?

Is that a laugh or is that a cry?

Mateo.

Is that a laugh or a cry?

Where's Laura?

Yeah, you don't like this position.

Are you going to crawl, Mateo?

Think you can crawl?

Come, come, come.

I see you, Mateo. Come.

Come on.

Hey!

Oh, detour.

A few weeks ago, he just started crawling,

and then as soon as he started,

he's just been going nonstop ever since.

So, yeah, he goes between rooms,

he climbed up the stairs the other day,
which I was shocked by.

Come, come, come.

And so I really
have to watch him now.

Hey, come on.

Come on. Hey, good boy.

Hey.

Good boy!

Come. Come here. Come.

Yeah, now I really need to be careful
with him, because...

Yeah, you're all over the place, bubs.

It's okay, come. Come, come.

It's okay, come.

More recently
he's getting more independent.

Just kind of going for it
and feeling confident

to just explore on his own.

Good boy!

You're on the move, bub.

All right, let's go.

Want to have your milk?
Want to go take a nap?

Night-night, Papa.

Over the years,

I've watched hundreds
and hundreds of babies crawl.

One of the things that I found out,

to my surprise and my frustration,

was that a baby who could demonstrate
that it could crawl on Monday

would not be able to crawl
on Tuesday or Wednesday or Thursday,

and then could crawl again on Friday,
and then not Saturday, Sunday.

So this raised the question
of whether there's a long period

when a baby can't crawl,

and then, like turning on a light switch,

all of a sudden now this baby can crawl?

Does it really work like that?

Well, the only way to know would be
to observe babies every single day

and see whether you turned on
the crawling switch.

This is my daughter, Lily,
when she was a baby.

And she was in my diary study,
and we tracked babies

from when they were born
until they were about 18, 20 months old.

We asked parents to track every
little skill that babies might display

on the way to being able to crawl.

This whole file is Lilly's data.

So, in March...

...Lily took
her first crawling steps.

So, on March 19th, she did a combat crawl,

and then we never saw it again.

And on March 28th she did a belly crawl,

and then not again

until April 1st.

Now Lilly is doing a whole variety

of little sort of crawling steps
of different types of crawls.

Sometimes they go away,

sometimes they stay
for several days in a row.

We learned that crawling
is incredibly variable

and incredibly creative,

and that every baby's trajectory
looks different from the other babies.

The whole idea of motor milestones,

where there's a kind
of orderly progression...

"First, babies can roll

and then they can sit up
and then they can crawl

and then they stand and then they cruise."

You know, it's been in the literature
for a century,

in every pediatrician's office,
in every parenting book or magazine.

It just really doesn't happen like that.

He's just done the same
words you've made.

Or noise.

Oh.

Get your balance right.

That is brilliant.

Our findings show

that there really is no
sort of steady march

from one stage to another.

Ah, success.

From whatever,
lifting your head up,

and then all the way to walking.

Good strong legs.

Instead, babies are acquiring their skills
in different orders,

and skills are sort of appearing
and disappearing and reappearing,

and then, bit by bit, babies gradually
make their way toward walking.

He's on the move
and there's no, sort of, turning back.

I don't think he's gonna crawl,
I think he's completely missed that stage.

Seeing other babies crawling
and getting places,

there was a thought of,
"It'd be nice if Pascoe could do that,"

but once we got the feeling that
he wasn't gonna crawl, it was just,

"All right, just let him stand up."

- Watch your head.
- On the table. Here.

Hey!

Where is it? Where'd it go?

He's just decided, "No, I like standing up

and I like moving around this way,
so I'm just gonna continue like this."

No. No.

- Yes.
- No.

It's just eagle eyes,
watching him all the time.

That's funny.

Making sure that he's not grabbing
something that he shouldn't grab.

Oi!

It's really important for parents to know
that crawling isn't mandatory.

It is not an obligatory stage
that babies have to do

before they begin walking.

And so, if your baby decides to crawl,

great.

What's that? It's a footy.

And if your baby finds
another solution for getting around,

like bum-shuffling, great.

And if your baby decides to just wait
and get up and walk, that's also great.

- That's it, that's it.
- Good cruise, good cruise.

Yes! Reach.

- Almost.
- Get closer. Good boy.

Babies all develop
in their own way.

One hand. Hey!

So just relax and enjoy

and watch your baby's
beautiful development.