While your child will still feel like your baby even when they’re 18 years old, what’s the official age range of a baby? How about a newborn or an infant? And what about a toddler? It may all feel like a blur, but each stage is distinct and unique!
In this article, we’ll share the specific age ranges of newborns, infants, babies, and toddlers, as well as typical social-emotional, motor, and cognitive milestones to look for within each. We’ll also offer you some suggestions for ways to nurture your child at whatever stage they’re in.
Key Takeaways
Table of contents
- Newborn, infant, and toddler age ranges
- Newborn, infant, and toddler milestones
- Newborn, infant, and toddler tips
Newborn, infant, and toddler age ranges
Let’s begin by clearing up the definition of the term “baby.” it doesn’t refer to a specific age range, but instead, encompasses all of the others. When you talk about your baby, you might be talking about your newborn, infant, or toddler.
What are the exact definitions of those three? Let’s take a look.
Newborn
The World Health Organization (WHO) defines a newborn as a baby in their first 28 days of life (basically their first four weeks, or one month). However, the informal, nonmedical definition is from birth through three months old.
Infant
An infant, according to the American Academy of Pediatrics (AAP), is defined as a baby between the ages of birth and two years old. But many people specify infants from birth through age 1.
Toddler
Finally, a toddler is typically between the ages of one to three.
Newborn, infant, and toddler milestones
You may have questions about your baby’s growth and development in the first three years of their life. And many of them probably begin with the word when: “When will my baby roll over?” “When will my baby sit up?” “When will my baby smile at me?”
Here’s a breakdown of social-emotional, motor, and cognitive developmental milestones that most babies will experience.
Newborn
Your newborn baby is learning about both the world and themselves. Everything is brand new! They will develop many skills by the time they reach the three-month mark. They may:
Social-emotional
- Self-soothe (sucking on hand)
- Smile (sometimes this is a reflex)
- Feel safe when they’re held
- Make eye contact
Motor
- Hold head up (briefly) when they’re in tummy time
- Move both arms and legs
- Open their hands
- Grab objects
Cognitive
- Track people and objects with their eyes
- Get fussy when they’re bored
- Respond to voices
- Make more sounds than just crying
Infant
Your baby continues to grow so much during this first year of life. Time will fly by, and you’ll be amazed at how much they change! Here’s what you can expect to see them do.
Social-emotional
- Cry when you leave (separation anxiety)
- Be shy around strangers
- Have favorite toys and books
- Enjoy music and games (think peek-a-boo)
Motor
- Wave and clap
-
Sit themselves up
- Pull up to stand with the help of furniture (couch) or a hand
- Take a few steps without support
Cognitive
- Copy movements
- Find hidden objects
- Babble
- Show excitement when something they like is about to happen
Toddler
Your little one is not so little anymore! By the time they turn three, you will see their personality blossoming. They may:
Social-emotional
- Get excited when they’re with other kids
- Look to you for cues about how to behave
- Notice when people are sad (learn about empathy)
- Calm themselves (like when you leave them at childcare)
Motor
- Kick and throw a ball
- Climb furniture and stairs
- Draw circles and straight lines
- Get dressed
Cognitive
- Follow two-step directions
- Play with more than one toy at a time
- Sort shapes and colors
- Build with blocks
Tips for Caring for your newborn, infant, and toddler
Your baby will develop at their own pace with their own priorities. For example, some babies work on motor skills earlier than others, while some focus on cognitive skills first. But you can play a pivotal part in creating a safe, stimulating, and nurturing space for them to flourish.
Newborn
1) Learn your newborn’s cues.
Even though your newborn’s vocal range spans from cry to…different cry (!), you can learn how to tell them apart. Is your baby hungry? Are they cold? Do they want to be held? You’ll pick up on these differences intuitively, but try focusing intentionally, too.
2) Hold your baby and then hold them some more.
A 2025 update on research related to skin-to-skin contact confirms that newborns who receive this contact within an hour after birth have an easier time regulating their body temperature, breathing, and heart rate.
And the benefits of skin-to-skin contact continue from there. Hold your baby close as often as you can. This intimate connection supports their brain development, sense of safety, and bond with you.
3) Give your newborn a safe place to sleep.
If you want to keep your baby close while they sleep, consider a Newton Bassinet & Bedside Sleeper. With an ultra-breathable mattress designed with our patented Wovenaire® technology, it’s both safe and comfortable for your little one in their first months of life.
Infant
1) Talk (and sing and read) to your baby.
Your baby finds your voice calming, so make sure their day is filled with it! When you sing to them, you help their brain and sensory development, and the more you read to them, the more they develop a strong literacy foundation.
Spend time engaging in “serve-and-return” with your infant, too. When they initiate a conversation with you, respond by smiling, nodding, and verbally answering. This builds brain architecture and communication skills.
2) Create a stimulating environment.
Support your baby’s natural curiosity by providing an environment filled with objects and activities to stimulate their senses. Pay attention to what excites them. If they love taking walks in the woods, do more of that. If they love to dance, make dancing part of your daily routine.
3) Keep your baby safe wherever you are.
Whether you’re at home, outside, or on the go, the Newton Travel Crib & Play Yard makes it easy to give your little (active!) one a big, safe space to both play and sleep. Like our mattresses, the play yard is ultra-breathable and washable.
Toddler
1) Give your toddler time to try tasks on their own.
It’s never too early to give your child a chance to practice some independence, especially when it comes to tasks.
By adding extra time into your daily schedule to allow your child to do things like dress themselves, feed a pet, and put away toys, you’re helping them build a sense of belonging and confidence.
2) Create routines.
Speaking of your daily schedule, make sure you’ve got one! Creating a routine (for the morning before school or at bedtime, for example) helps your toddler feel safe. When they know what to expect and understand their part in the process, they feel free to explore their world.
3) Encourage creative, active play.
Creative, active play helps your toddler build physical coordination while allowing them an outlet to explore their emotions in a safe, imaginative way. It also develops critical thinking, spatial awareness, problem-solving skills, and empathy.
Try encouraging this kind of play with a Newton X Figgy Play Couch. With four base cushions, two rectangles, and one wedge, your child will have endless fun building, climbing, and pretending. And you can upcycle your Newton mattress into it, too!
Support your baby through every stage with Newton
Your baby’s first three years are full of learning, exploring, creating, and making connections. We hope this overview of their social-emotional, motor, and cognitive milestones gives you a sense of what to expect, but don’t forget: each child has their own path and pace.
The more you understand your baby, the more you can support their growth and nurture their full potential. And Newton is here to help! We create our products to keep your baby healthy and safe, and we always have your peace of mind on our minds!
Frequently asked questions
What do I do if my baby hits their milestones early or late?
Most of the time, the right thing to do is…nothing! Every baby develops at their own speed and with their own focus. Your baby might talk early but not walk until after they’re one. Or they might develop motor skills faster than their verbal skills. Try to be patient and trust their process.
That said, if you’re ever worried about your baby’s development, it’s always a good idea to consult with their pediatrician.
What if my baby was born prematurely?
If your baby was born earlier than you expected, track their developmental milestones by using your original due date. Many premature babies need a little extra time to reach their milestones.
When will my baby recognize their name?
Babies typically recognize their own name by the time they’re five months old. Reinforce this awareness by using their name when you do things together (“Mommy and [your baby’s name] are going for a walk”) or when you’re pointing things out (“Look at the bird, [your baby’s name].”
The more you use your baby’s name in different contexts, the more they’ll make the connection between it and who they are!
