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236
•
Updated Mar 25, 2026
•
Courtney Fowler
@courtneyfowler
Ever wondered how your body develops from birth to old... Show more





Your body is constantly changing, but there's actually two different processes happening. Growth is the simple stuff - getting taller, heavier, and physically bigger. Development is way more interesting - it's how you learn to control your body and master new skills.
Physical development follows some pretty clever patterns that work the same for everyone. You develop from top to toe (head control before walking) and from inner to outer (arm control before finger precision). This is why babies can wave their arms around ages before they can pick up tiny objects.
Everyone develops at their own pace though. Some infants zoom through milestones whilst others take their time - and both are completely normal. The important thing is that the skills eventually develop, not exactly when they happen.
Quick Tip: Remember PIES - Physical, Intellectual, Emotional, and Social development all happen together and affect each other.

This is when the most dramatic changes happen - babies go from helpless newborns to walking, climbing toddlers in just two years! Gross motor skills (big movements) and fine motor skills (precise movements) develop alongside each other.
In the first six months, babies learn to hold their heads up and roll over. They can grip a rattle but can't really control it properly yet. By their first birthday, most babies are sitting independently and starting to walk whilst holding furniture.
The 12-24 month period is when things get exciting. Toddlers master walking, start climbing stairs, and can kick balls around. Their hand control improves dramatically - they can build towers with blocks, scribble with crayons, and feed themselves with a spoon.
Remember: These are average ages - some babies walk at 10 months, others at 15 months, and both are perfectly normal!

By age 8, most children have mastered the basic physical skills they'll use for life. This stage is all about refining movements and becoming more coordinated and confident with their bodies.
Early childhood sees major improvements in balance and coordination. Two-year-olds can walk upstairs properly, and by three they're jumping off low steps. Their hand skills become much more precise - they can draw recognisable shapes and turn book pages without tearing them.
The detailed chart shows exactly what to expect at each age, but the key point is that children become increasingly independent. They're building the foundation skills needed for sports, writing, and all the physical activities they'll enjoy later.
Study Smart: Focus on the general progression rather than memorising exact ages - exams often test your understanding of the patterns, not specific months.

Illness doesn't just make you feel rubbish - it can seriously impact development across all four PIES areas. Understanding these connections is crucial for supporting people through health challenges.
Physical and intellectual impacts are often linked. Missing school due to illness affects learning, whilst problems with memory and concentration make decision-making harder. Tiredness and mobility issues can completely prevent physical activity.
The emotional and social consequences can be just as serious. Illness often causes worry and stress, leading to low self-esteem and loss of independence. This particularly affects older adults who may become isolated from friends and family.
Relationships can suffer when illness prevents socialising or building new connections. Sometimes the stress of managing health problems can even cause existing relationships to break down.
Exam Focus: Questions often ask about the knock-on effects of illness - remember that problems in one PIES area usually affect the others too.
Our AI Companion is a student-focused AI tool that offers more than just answers. Built on millions of Knowunity resources, it provides relevant information, personalised study plans, quizzes, and content directly in the chat, adapting to your individual learning journey.
You can download the app from Google Play Store and Apple App Store.
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
App Store
Google Play
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE Knowunity AI. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE Knowunity AI. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
Courtney Fowler
@courtneyfowler
Ever wondered how your body develops from birth to old age? Physical development is all about how we grow bigger and stronger, while also learning to control our movements - from a baby's first steps to playing sports as a... Show more

Access to all documents
Improve your grades
Join milions of students
Your body is constantly changing, but there's actually two different processes happening. Growth is the simple stuff - getting taller, heavier, and physically bigger. Development is way more interesting - it's how you learn to control your body and master new skills.
Physical development follows some pretty clever patterns that work the same for everyone. You develop from top to toe (head control before walking) and from inner to outer (arm control before finger precision). This is why babies can wave their arms around ages before they can pick up tiny objects.
Everyone develops at their own pace though. Some infants zoom through milestones whilst others take their time - and both are completely normal. The important thing is that the skills eventually develop, not exactly when they happen.
Quick Tip: Remember PIES - Physical, Intellectual, Emotional, and Social development all happen together and affect each other.

Access to all documents
Improve your grades
Join milions of students
This is when the most dramatic changes happen - babies go from helpless newborns to walking, climbing toddlers in just two years! Gross motor skills (big movements) and fine motor skills (precise movements) develop alongside each other.
In the first six months, babies learn to hold their heads up and roll over. They can grip a rattle but can't really control it properly yet. By their first birthday, most babies are sitting independently and starting to walk whilst holding furniture.
The 12-24 month period is when things get exciting. Toddlers master walking, start climbing stairs, and can kick balls around. Their hand control improves dramatically - they can build towers with blocks, scribble with crayons, and feed themselves with a spoon.
Remember: These are average ages - some babies walk at 10 months, others at 15 months, and both are perfectly normal!

Access to all documents
Improve your grades
Join milions of students
By age 8, most children have mastered the basic physical skills they'll use for life. This stage is all about refining movements and becoming more coordinated and confident with their bodies.
Early childhood sees major improvements in balance and coordination. Two-year-olds can walk upstairs properly, and by three they're jumping off low steps. Their hand skills become much more precise - they can draw recognisable shapes and turn book pages without tearing them.
The detailed chart shows exactly what to expect at each age, but the key point is that children become increasingly independent. They're building the foundation skills needed for sports, writing, and all the physical activities they'll enjoy later.
Study Smart: Focus on the general progression rather than memorising exact ages - exams often test your understanding of the patterns, not specific months.

Access to all documents
Improve your grades
Join milions of students
Illness doesn't just make you feel rubbish - it can seriously impact development across all four PIES areas. Understanding these connections is crucial for supporting people through health challenges.
Physical and intellectual impacts are often linked. Missing school due to illness affects learning, whilst problems with memory and concentration make decision-making harder. Tiredness and mobility issues can completely prevent physical activity.
The emotional and social consequences can be just as serious. Illness often causes worry and stress, leading to low self-esteem and loss of independence. This particularly affects older adults who may become isolated from friends and family.
Relationships can suffer when illness prevents socialising or building new connections. Sometimes the stress of managing health problems can even cause existing relationships to break down.
Exam Focus: Questions often ask about the knock-on effects of illness - remember that problems in one PIES area usually affect the others too.
Our AI Companion is a student-focused AI tool that offers more than just answers. Built on millions of Knowunity resources, it provides relevant information, personalised study plans, quizzes, and content directly in the chat, adapting to your individual learning journey.
You can download the app from Google Play Store and Apple App Store.
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
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Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
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Explore key theories of cognitive development by Piaget and Chomsky, focusing on stages of cognitive growth, schema theory, and language acquisition. This summary highlights essential concepts such as assimilation, accommodation, and the implications of these theories on understanding child development. Ideal for HSC Unit 1 students seeking a clear overview of intellectual development theories.
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App Store
Google Play
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE Knowunity AI. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user
The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.
Stefan S
iOS user
This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.
Samantha Klich
Android user
Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.
Anna
iOS user
Best app on earth! no words because it’s too good
Thomas R
iOS user
Just amazing. Let's me revise 10x better, this app is a quick 10/10. I highly recommend it to anyone. I can watch and search for notes. I can save them in the subject folder. I can revise it any time when I come back. If you haven't tried this app, you're really missing out.
Basil
Android user
This app has made me feel so much more confident in my exam prep, not only through boosting my own self confidence through the features that allow you to connect with others and feel less alone, but also through the way the app itself is centred around making you feel better. It is easy to navigate, fun to use, and helpful to anyone struggling in absolutely any way.
David K
iOS user
The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!
Sudenaz Ocak
Android user
In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.
Greenlight Bonnie
Android user
very reliable app to help and grow your ideas of Maths, English and other related topics in your works. please use this app if your struggling in areas, this app is key for that. wish I'd of done a review before. and it's also free so don't worry about that.
Rohan U
Android user
I know a lot of apps use fake accounts to boost their reviews but this app deserves it all. Originally I was getting 4 in my English exams and this time I got a grade 7. I didn’t even know about this app three days until the exam and it has helped A LOT. Please actually trust me and use it as I’m sure you too will see developments.
Xander S
iOS user
THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE Knowunity AI. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮
Elisha
iOS user
This apps acc the goat. I find revision so boring but this app makes it so easy to organize it all and then you can ask the freeeee ai to test yourself so good and you can easily upload your own stuff. highly recommend as someone taking mocks now
Paul T
iOS user