Your toddler’s brain development from age 1 to age 2


Welcome to the first year of toddlerhood! Your little one is becoming a little person of their own. They’ll start walking and talking, assert their independence (quite forcefully, at time!), and learn to make friends with other children, among other noteworthy milestones.

The rapid brain development that began in pregnancy and continued rapidly throughout the first year of your baby’s life will also characterize their toddlerhood. Your toddler’s brain will grow even more complex, paving the way for the next phase of your child’s development: Their newly-formed sense of identity, social and emotional understanding, and the ability to communicate.

Read on for the expert-backed guide on your toddler’s brain development and milestones between their first and second birthdays.

What’s happening inside the brain

Between the ages of one and two, complex brain systems start interacting more with each other “From age one to two, the brain develops at an incredibly rapid rate,” says Dr. Rebekah Diamond, MD, a pediatrician in clinical practice and the author of Parent Like a Pediatrician.

“Connections are being formed between brain cells but also being pruned, meaning that the most helpful and important connections are maintained while others are weeded out. All throughout childhood (especially the infant and toddler years) is filled with exponential growth in language, motor, social, and problem-solving abilities.”

The importance of sleep

Your toddler needs ample sleep during this age to keep up with all the new skills they’re developing, and everything they’re learning about the world around them.

“Sleep is a key ingredient for the developing brain,” notes Dr. Stern. “The CDC recommends 11 to 14 hours of sleep per day (including naps) for toddlers between one and two years of age. Getting sufficient good-quality (uninterrupted) sleep on a reasonably regular schedule is important for children’s brains to grow.”

And it’s not just nighttime sleep that matters — every nap is a building block for your toddler’s rapid development. “Regular sleep and napping have been linked to children’s ability to learn new things, remember past events, engage in positive social behavior, and manage their emotions,” says Dr. Stern. In fact, “sleep researchers are discovering that glial cells in the central nervous system actually help ‘clean’ our brain of metabolites during deep sleep — and young developing brains need this, too!”

Cognitive development and memory

Cognitive development is the term for how your child thinks, explores, and figures things out. As their brain develops, so does your child’s problem-solving skills, self-knowledge, and awareness of their surroundings — all of which help your toddler better understand the world around them.

12 to 18 months

Toddlers this age love trial and error and experimentation. Watch as they test out a variety of actions, noises, and expressions to see what gets attention from their parents or caregivers!

For example, your tot might notice you smile or laugh when they clap their hands. They might then do it repeatedly to elicit the same positive reaction from you. (Needless to say, funny faces are a big hit with babies this age.)

18 to 24 months

By this age, your child will start understanding that symbols and words represent objects and events. For example, when they see a cat in a picture book or in the street, they might say “cat” or “meow.”

By the time your child is two years old, they can:

  • Recognize themselves in the mirror (which means they see themselves as an individual now).
  • Imitate the actions and words of parents or caregivers. For example, if you have a particular habit, like walking with your hands behind your back, you might notice your toddler walking around the house in a similar manner.
  • Understand your words and commands, and respond to them.
  • Begin to match similar objects and recognize and find familiar things in storybooks with some help.
  • Understand the difference between “you” and “me.”

Social and emotional development milestones

“The second year of life is a period of rapid cognitive, social, and emotional development,” says Dr. Stern. “During this time, babies begin to walk, talk, point, imitate others, recall past events, interact socially and help others, recognize other people and express excitement to see them, and develop a sense of self.”

Providing your toddler with a safe and encouraging environment will impact how they explore and see the world around them.

According to Dr. Stern, one of the most critical developments in children is the formation of strong emotional attachments to one or more caregivers. “Infants who learn from experience that they can trust and depend on their caregivers as a secure ‘home base’ are more confident exploring their world. They also show better self-control, calm more easily after stress, and are likelier to be kind to others.”

These advances in social and emotional abilities are supported by dramatic changes in the brain. “This includes rapid increases in neural connections in auditory and visual sensory areas and growth in overall brain size — by age two, your toddler’s brain will already be about 80% of the size of an adult brain,” says Dr. Stern.

Did you know?
“As early as 18 months, infants who show more facial expressions of empathic concern for someone in distress are more likely to offer help to that person,” says Dr. Stern.


Did you know?

“As early as 18 months, infants who show more facial expressions of empathic concern for someone in distress are more likely to offer help to that person,” says Dr. Stern.

By the time your child is two years old, they may:

  • Start saying “no.” If  bedtime, nap time, and meals  are met with your toddler’s new favorite word, take it as a positive sign that your toddler’s cognitive development is on track.
  • Grasp the concept of sharing, while still struggling  to let someone else play with their toys or have a bite of their meal.
  • Experience complex emotions like jealousy when they feel that you are giving attention to someone else, for example a younger sibling. Be patient with your toddler as they figure out these emotions.
  • Begin playing with other kids their age. This will mark the beginning of their social development.
  • Display affection by hugging and kissing parents, caregivers, pets, and anyone with whom they feel safe.
  • Show frustration easily by throwing  tantrums and displaying aggressive behaviors.

Here are some tips to help your mini-me develop their own sense of identity:

  • Around 18 months, toddlers start to develop self-awareness, autonomy, and a sense of identity. Give your tot more agency and choice in their activities (“Do you want to take a bath now or later?” “Which toy shall we play with first?”), as well as opportunities to explore in a safe environment.
  • Cognitively, toddlers are still learning that other people have beliefs, preferences, and perspectives that may differ from their own. You can encourage your child’s social understanding of others  through reading, storytelling, or playing games involving different characters.
  • Help your child navigate social interactions by noting other children’s different intentions and feelings (“I think your brother might want to play with a different toy”). Have them practice sharing with others (“Can you let your friend have a turn?”). Their developing sense of self grows through these social interactions, laying the foundation for empathy and prosocial behavior.

Motor development milestones

You’ll see an advanced development in your child’s motor skills during this age. The cerebellum, located at the back of the brain, is responsible for your child’s motor activity — from walking to learning how to hold a crayon. The cerebellum continues developing during this age, leading to significant motor milestones.

Here are some motor developments that you will observe in your toddler between ages  one and two:

12-18 months

  • They can clap their hands together.
  • They are capable of putting their toys into containers.
  • They can isolate the index finger with the other fingers closed.
  • If you give them a crayon, they might start scribbling with it (but their grip might not be perfect yet).
  • They will start using a cup or spoon during their meals.

18-24 months

  • They can build a block tower and arrange different blocks according to their shapes and sizes.
  • They can put rings on a ring stacker.
  • If you hand them a picture book, they’ll be able to turn pages of the book one at a time.
  • By the time they are two, they will start holding crayons with their fingertips and thumb.
  • Your toddler will start walking independently around this time.
  • They can probably go downstairs while putting both feet on each step before moving to the next step.

Speech development milestones

Babies brains are especially sensitive to the words they hear in their environment — and they pay particular attention to words spoken by caregivers. “This sensitivity to language means that your infant is much faster to learn new languages than us adults!” says Dr. Stern.

As early as the second year of life, language processing is “left-lateralized” in children just as in adults — meaning that much of the action takes place in the brain’s left hemisphere. Children can follow simple instructions around 12 months as their temporal lobe develops.

But what’s happening inside your child’s brain as they develop the ability to talk?

Dr. Stern explains, “Neural activity in a brain region called Wernicke’s area is associated with understanding language, and activity in Broca’s area is associated with producing language. As children practice speech sounds, the neural connections linking Broca’s area to the motor cortex strengthen, supporting their newfound ability to talk.”

Parents can expect their toddler’s speech to develop slowly and in (extremely cute) stages. “If you hear your child babbling, it isn’t just to make noise — they’re actively practicing their speech sounds!” says Dr. Stern. “Every child develops language at their own pace, but typically by 18 to 24 months, toddlers can say at least 50 words (but they understand much more) and may begin to connect two to three words together (‘You play!’).”

Dr. Stern’s tip for parents: You can grow your child’s vocabulary each day by talking and singing with them, practicing conversational turn-taking, and elaborating on the few words your child says. (For example, if your child says “Ball?” you could say, “Yes, this is a nice big ball, isn’t it?”). It helps children form the neural connections (or synapses) that are the building blocks of language development.

How to boost brain development during this stage

Cognitive development:

  • Encourage pretend play with toys to help spark creativity in your child as they make up stories and characters.
  • Give your kiddo some crayons and paper to draw on. Paint and play-dough also foster creativity.
  • Give them puzzles and blocks to help them exercise those problem-solving skills.
  • Sing rhymes or songs in the car when they are driving with you.

Social and emotional development:

  • Praise your child and show affection in both words and actions by giving them hugs and kisses for positive behavior and achievements.
  • Deal with their temper tantrums peacefully and calmly.
  • Help them understand and identify their emotions. For example, “You are happy when we go to the beach,” or “You felt upset when you didn’t get to eat candy in the grocery store.”
  • Encourage them more for good behavior than punishing their unwanted behaviors.

Motor development:

  • Child-proof your home so they can move around and explore their surroundings safely.
  • Encourage your kiddo to drink from a cup and use a spoon during meals.
  • Encourage them to open and close drawers and doors while they are in the kitchen or bedroom with you.
  • Involve playful physical activities in their playtime, like a walk on the beach or in the park, or dancing to their favorite songs. 

Speech development:

  • Read books to your toddler, have them look at pictures in a storybook, and make up stories. Ask them questions about the story or the pictures.
  • Sing songs and rhymes together. This will help your toddler improve their memory and speech. Kids often learn new words from the songs or poems they hear.
  • Talk to your child about the activities that you’re doing together.
  • Start using words to identify different emotions and feelings. This will help your toddler communicate.

Crib Notes

Cradlewise is the only smart sleeper designed for use for 24 months. We’re here to support your child’s sleep from the day you bring your baby home until they reach their second birthday.


Crib Notes

Cradlewise is the only smart sleeper designed for use for 24 months. We’re here to support your child’s sleep from the day you bring your baby home until they reach their second birthday.

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