Understanding your baby's development from birth to 9 months helps... Show more
Sign up to see the contentIt's free!
Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Subjects
Responding to change (a2 only)
Infection and response
Homeostasis and response
Energy transfers (a2 only)
Cell biology
Organisms respond to changes in their internal and external environments (a-level only)
Biological molecules
Organisation
Substance exchange
Bioenergetics
Genetic information & variation
Inheritance, variation and evolution
Genetics & ecosystems (a2 only)
Ecology
Cells
Show all topics
Britain & the wider world: 1745 -1901
1l the quest for political stability: germany, 1871-1991
The cold war
Inter-war germany
Medieval period: 1066 -1509
2d religious conflict and the church in england, c1529-c1570
2o democracy and nazism: germany, 1918-1945
1f industrialisation and the people: britain, c1783-1885
1c the tudors: england, 1485-1603
2m wars and welfare: britain in transition, 1906-1957
World war two & the holocaust
2n revolution and dictatorship: russia, 1917-1953
2s the making of modern britain, 1951-2007
World war one
Britain: 1509 -1745
Show all topics
60
•
7 Dec 2025
•
Rox Foster
@roxyfoster_etam
Understanding your baby's development from birth to 9 months helps... Show more










Child development isn't just about getting bigger - it's a complete transformation that happens during your baby's first months of life. Your little one will go through incredible changes in three main stages: 1-3 months, 4-6 months, and 7-9 months.
Each stage brings exciting new abilities and behaviours. You'll watch as your baby grows stronger, more aware, and more interactive with the world around them.
Remember: Every baby develops at their own unique pace, so don't worry if your child reaches milestones slightly earlier or later than expected.

Growth and development covers much more than just physical changes from infancy through adolescence. It includes emotional changes, personality development, behaviour patterns, thinking skills, and speech development.
Think of it as your baby building a complete toolkit for life. Physical growth gives them the strength to move and explore, whilst emotional and cognitive development helps them understand and interact with their environment.
This holistic approach to development means every cuddle, conversation, and playtime contributes to your baby's overall progress.
Key Point: Development happens in all areas simultaneously - physical, emotional, social, and cognitive growth all work together.

Milestones are the key achievements children reach as they learn to play, speak, and move. These markers help you track your baby's progress and know what to expect next.
For physical growth, expect steady changes: babies typically gain 1.5-2 pounds each month and grow about half an inch in height monthly. Their head size also increases by roughly 0.5 inches each month to accommodate their rapidly developing brain.
These measurements give you a baseline, but remember that healthy babies come in all sizes. Your health visitor will track these changes to ensure everything's progressing well.
Did You Know: A baby's head grows quickly in the first year because their brain doubles in size during this time!

Your newborn's reflexes begin to disappear as intentional movements take over. This is when your baby starts becoming more aware of their body and surroundings.
Watch for these exciting developments: turning their head side to side when on their tummy, bringing hands or objects to their mouth, and actually looking at their own hands with fascination. They'll start following lights, faces, and moving objects with their eyes.
Your baby will also begin grasping and releasing - holding a rattle briefly before dropping it. They're learning to listen to different sounds and will open and close their hands as they discover how their body works.
Milestone Alert: When your baby starts bringing objects to their mouth, they're not just exploring - they're learning about texture, temperature, and taste!

Your baby's early communication starts with adorable coos and vowel sounds as they begin imitating what they hear. This is the foundation of all future speech development.
Purposeful crying develops during this stage - you'll notice different cries for hunger, tiredness, or needing a nappy change. Your baby is learning to communicate their needs effectively.
For social understanding, expect responsive smiles when you interact with them. Your baby will move their arms, legs, and body in rhythm with your voice, showing they're actively engaging with social contact.
Communication Tip: Those early coos and babbles are your baby's first attempts at conversation - always respond to encourage their communication skills!

Face-to-face interaction is crucial - hold your baby close, make eye contact, and talk with a soothing, animated voice during daily activities like dressing, bathing, and feeding.
Provide sensory experiences with rattles and soft toys that make different sounds. Let them hear various sounds like wind chimes, ticking clocks, or gentle music to stimulate their developing hearing.
Visual development benefits from bright pictures, especially black and white images that are easier for young babies to focus on. Always use your baby's name when talking to them - this helps with recognition and bonding.
Development Boost: Talking to your baby throughout daily routines helps them learn language patterns and strengthens your emotional connection.

Growth patterns shift slightly as your baby enters this new phase. Weight gain slows to about 1/4 to 1/2 pound each month, whilst height increases by roughly 1/2 to 1 inch monthly.
Head growth continues at about 1/2 inch each month, supporting continued brain development. This steadier growth pattern is completely normal as your baby's body adjusts to their increasing activity levels.
These measurements help healthcare providers ensure your baby is developing healthily. Don't worry if your baby doesn't match these averages exactly - healthy babies come in many different sizes and growth patterns.
Growth Fact: Slower weight gain at this stage often coincides with increased movement and activity as babies become more mobile!

Motor development takes a big leap as primitive reflexes like the Moro, grasp, and rooting reflexes fade away. Your baby now has much better head control and can balance their head steadily.
Sitting skills emerge as your baby learns to sit with support - this opens up a whole new perspective on the world around them.
To boost development, repeat sounds and smile back at your baby, laugh together, and spend plenty of time on the floor playing. These interactions support both emotional security and physical development.
Sitting Milestone: Once your baby can sit with support, they can use both hands to explore toys and objects more effectively!

Rolling skills become effortless as your baby easily rolls from front to back and back to front. They can now sit leaning forward on their hands and will bounce excitedly when supported in a standing position.
For emotional security, provide safe toys that make noise when shaken or hit - these cause-and-effect toys teach important learning concepts whilst entertaining your baby.
Interactive activities become more engaging: play in front of a mirror whilst calling your baby by name, and establish a daily routine of showing picture books and reading stories together.
Reading Tip: Even though your baby can't understand stories yet, daily reading builds language skills and creates positive associations with books from an early age!
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.
Quotes from every main character
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 THE SCHOOLGPT. 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 THE SCHOOLGPT. 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
Rox Foster
@roxyfoster_etam
Understanding your baby's development from birth to 9 months helps you support their amazing journey of growth. Every baby develops at their own pace, but knowing what to expect can help you celebrate each milestone and encourage their progress.

Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Child development isn't just about getting bigger - it's a complete transformation that happens during your baby's first months of life. Your little one will go through incredible changes in three main stages: 1-3 months, 4-6 months, and 7-9 months.
Each stage brings exciting new abilities and behaviours. You'll watch as your baby grows stronger, more aware, and more interactive with the world around them.
Remember: Every baby develops at their own unique pace, so don't worry if your child reaches milestones slightly earlier or later than expected.

Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Growth and development covers much more than just physical changes from infancy through adolescence. It includes emotional changes, personality development, behaviour patterns, thinking skills, and speech development.
Think of it as your baby building a complete toolkit for life. Physical growth gives them the strength to move and explore, whilst emotional and cognitive development helps them understand and interact with their environment.
This holistic approach to development means every cuddle, conversation, and playtime contributes to your baby's overall progress.
Key Point: Development happens in all areas simultaneously - physical, emotional, social, and cognitive growth all work together.

Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Milestones are the key achievements children reach as they learn to play, speak, and move. These markers help you track your baby's progress and know what to expect next.
For physical growth, expect steady changes: babies typically gain 1.5-2 pounds each month and grow about half an inch in height monthly. Their head size also increases by roughly 0.5 inches each month to accommodate their rapidly developing brain.
These measurements give you a baseline, but remember that healthy babies come in all sizes. Your health visitor will track these changes to ensure everything's progressing well.
Did You Know: A baby's head grows quickly in the first year because their brain doubles in size during this time!

Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Your newborn's reflexes begin to disappear as intentional movements take over. This is when your baby starts becoming more aware of their body and surroundings.
Watch for these exciting developments: turning their head side to side when on their tummy, bringing hands or objects to their mouth, and actually looking at their own hands with fascination. They'll start following lights, faces, and moving objects with their eyes.
Your baby will also begin grasping and releasing - holding a rattle briefly before dropping it. They're learning to listen to different sounds and will open and close their hands as they discover how their body works.
Milestone Alert: When your baby starts bringing objects to their mouth, they're not just exploring - they're learning about texture, temperature, and taste!

Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Your baby's early communication starts with adorable coos and vowel sounds as they begin imitating what they hear. This is the foundation of all future speech development.
Purposeful crying develops during this stage - you'll notice different cries for hunger, tiredness, or needing a nappy change. Your baby is learning to communicate their needs effectively.
For social understanding, expect responsive smiles when you interact with them. Your baby will move their arms, legs, and body in rhythm with your voice, showing they're actively engaging with social contact.
Communication Tip: Those early coos and babbles are your baby's first attempts at conversation - always respond to encourage their communication skills!

Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Face-to-face interaction is crucial - hold your baby close, make eye contact, and talk with a soothing, animated voice during daily activities like dressing, bathing, and feeding.
Provide sensory experiences with rattles and soft toys that make different sounds. Let them hear various sounds like wind chimes, ticking clocks, or gentle music to stimulate their developing hearing.
Visual development benefits from bright pictures, especially black and white images that are easier for young babies to focus on. Always use your baby's name when talking to them - this helps with recognition and bonding.
Development Boost: Talking to your baby throughout daily routines helps them learn language patterns and strengthens your emotional connection.

Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Growth patterns shift slightly as your baby enters this new phase. Weight gain slows to about 1/4 to 1/2 pound each month, whilst height increases by roughly 1/2 to 1 inch monthly.
Head growth continues at about 1/2 inch each month, supporting continued brain development. This steadier growth pattern is completely normal as your baby's body adjusts to their increasing activity levels.
These measurements help healthcare providers ensure your baby is developing healthily. Don't worry if your baby doesn't match these averages exactly - healthy babies come in many different sizes and growth patterns.
Growth Fact: Slower weight gain at this stage often coincides with increased movement and activity as babies become more mobile!

Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Motor development takes a big leap as primitive reflexes like the Moro, grasp, and rooting reflexes fade away. Your baby now has much better head control and can balance their head steadily.
Sitting skills emerge as your baby learns to sit with support - this opens up a whole new perspective on the world around them.
To boost development, repeat sounds and smile back at your baby, laugh together, and spend plenty of time on the floor playing. These interactions support both emotional security and physical development.
Sitting Milestone: Once your baby can sit with support, they can use both hands to explore toys and objects more effectively!

Access to all documents
Improve your grades
Join milions of students
By signing up you accept Terms of Service and Privacy Policy
Rolling skills become effortless as your baby easily rolls from front to back and back to front. They can now sit leaning forward on their hands and will bounce excitedly when supported in a standing position.
For emotional security, provide safe toys that make noise when shaken or hit - these cause-and-effect toys teach important learning concepts whilst entertaining your baby.
Interactive activities become more engaging: play in front of a mirror whilst calling your baby by name, and establish a daily routine of showing picture books and reading stories together.
Reading Tip: Even though your baby can't understand stories yet, daily reading builds language skills and creates positive associations with books from an early age!
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.
2
Smart Tools NEW
Transform this note into: ✓ 50+ Practice Questions ✓ Interactive Flashcards ✓ Full Mock Exam ✓ Essay Outlines
Quotes from every main character
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 THE SCHOOLGPT. 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 THE SCHOOLGPT. 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