Developmental milestones from 3 months to 17 years

Each age has two short lists. The first shows what most children do around that age. The second shows signs that need a check by your doctor.

If your child does not do one thing on the first list yet, watch, play and mention it at the next visit. If you see something on the second list, call your doctor. These signs are not a diagnosis. Many children who show one of them develop well.

Walking early does not make a child smarter. Your doctor looks for steady progress.

For premature babies, use corrected age. A baby born 2 months early is compared with 4-month-olds at 6 months. Read our guide to corrected age.

Most babies:

• lift the head and chest when lying on the tummy
• smile back at familiar faces
• coo and make vowel sounds
• watch faces and follow moving things with their eyes
• bring their hands to the mouth

Call your doctor if your baby:

• does not react to loud sounds
• does not follow moving things with the eyes
• does not smile at people
• cannot hold the head up when held upright

Most babies:

• roll over both ways
• begin to sit without support
• reach for toys and grab them
• respond to their name
• babble vowel sounds like “ah”, “eh” and “oh”
• are curious and try to get things out of reach

Call your doctor if your baby:

• does not try to get things within reach
• shows no affection for the people who care for them
• does not react to sounds around them
• has trouble bringing things to the mouth
• does not laugh or squeal
• does not roll over either way
• seems very stiff, or very floppy like a rag doll

Most babies:

• sit without support
• crawl or scoot in some way
• pull up to stand
• babble sounds like “mama” and “baba”
• play peekaboo
• point at things with a finger

Call your doctor if your baby:

• does not bear weight on the legs with support
• does not sit with help
• does not babble “mama”, “baba” or “dada”
• does not play any back-and-forth games
• does not respond to their name
• does not seem to know familiar people
• does not look where you point

Most babies:

• pull up to stand and may take first steps
• wave bye-bye
• say “mama” and “dada” for the right person
• try to repeat words you say
• bang two things together
• follow simple requests like “come here”
• eat finger foods

Call your doctor if your baby:

• does not crawl
• cannot stand when held
• does not look for things they saw you hide
• does not say single words like “mama” or “dada”
• does not wave or shake the head
• does not point at things

Most children:

• walk alone
• say several single words
• stack two blocks
• scribble with a crayon
• drink from a cup with help
• show you things they like
• play with toys the usual way, like rolling a ball or pushing a car

Call your doctor if your child:

• does not walk
• says no words other than “mama” or “dada”
• does not show you things to share interest

Most children:

• walk well and may run a little
• say three or more words besides “mama” and “dada”
• point to body parts when asked
• pretend to feed a doll or a soft toy
• help take off their clothes
• drink from a cup without help
• eat with a spoon

Call your doctor if your child:

• does not point to show you things
• cannot walk
• does not know what common things are for, like a phone, a brush or a spoon
• does not copy others
• is not learning new words
• has fewer than 6 words

Most children:

• put two words together, like “more milk” or “go car”
• follow simple two-step instructions
• point to pictures or objects when you name them
• run
• climb on and off furniture
• begin to sort shapes and colors
• test limits. Saying “no” is normal at this age.

Call your doctor if your child:

• does not use two-word phrases
• does not know what to do with common things like a brush, a phone or a spoon
• does not copy actions or words
• does not follow simple instructions
• does not walk steadily

Most children:

• speak in sentences of three words or more
• say their first name, their age, and whether they are a boy or a girl
• name a friend
• hold a short conversation of two or three sentences
• pedal a tricycle
• climb stairs one foot per step
• play pretend with dolls, animals and people
• work toys with buttons and levers

Call your doctor if your child:

• falls a lot or has trouble with stairs
• drools or speaks very unclearly
• cannot work simple toys
• does not speak in sentences
• does not understand simple instructions
• does not make eye contact

Most children:

• hop, and stand on one foot for up to 2 seconds
• catch a bounced ball most of the time
• pour, cut with supervision and mash their own food
• tell stories
• use some basic grammar
• play together with other children
• name some colors and some numbers
• understand the idea of counting

Call your doctor if your child:

• cannot jump in place
• has trouble scribbling
• shows no interest in games with others or in pretend play
• ignores other children, or does not respond to people outside the family
• fights dressing, sleep or the toilet very strongly
• cannot retell a favorite story
• does not follow instructions with three parts
• speaks so unclearly that strangers cannot understand

Most children:

• stand on one foot for 10 seconds or longer
• hop, and may skip
• use the toilet on their own
• count 10 or more things
• draw a person with at least 6 body parts
• write some letters or numbers
• want to please their friends and be like them
• speak very clearly
• tell a simple story in full sentences

Call your doctor if your child:

• does not show a wide range of emotions
• is unusually fearful, aggressive, shy or sad
• is unusually withdrawn and inactive
• cannot focus on one activity for more than 5 minutes
• does not respond to people, or only on the surface
• cannot tell what is real from what is pretend
• does not play a variety of games
• cannot say their first and last name
• does not use plurals or the past tense correctly
• does not talk about their day
• does not draw pictures
• cannot brush teeth, wash and dry hands or undress without help

Most children:

• hop, skip and balance on one foot
• ride a bicycle, with or without training wheels
• begin to read simple words and write their own name
• follow instructions with several steps, at home and at school
• play group games and follow the rules
• have close friends and care about being included
• talk about their feelings and about their day
• start to ask questions about the future
• dress, wash, brush their teeth and use the toilet on their own

Call your doctor if your child:

• cannot follow simple two-step instructions
• speaks so unclearly that adults outside the family cannot understand
• does not recognize any letters or numbers yet
• avoids or refuses school most days
• has severe tantrums or aggression that disrupt daily life
• keeps away from other children and shows little interest in friends
• cannot dress, use the toilet or wash their hands without help

Most children:

• read on their own for short stretches, and still enjoy being read to
• write short stories and simple paragraphs
• think through problems that have more than one step
• plan and finish small projects, like a drawing or a model
• have a best friend, often someone who likes the same things
• understand fairness, rules and consequences, and sometimes test the limits
• follow their morning and bedtime routines with reminders
• do small chores, like setting the table or making their bed
• talk about their own feelings and about other people’s
• take part in a sport, dance, music or a similar activity

Call your doctor if your child:

• reads, writes or does math well below the level of the class
• avoids or refuses school for weeks at a time
• is sad most of the time, or loses interest in things they enjoyed
• talks about hurting themselves. Call the same day.
• is aggressive toward people or animals, and it is getting worse
• has no close friends and keeps away from other children
• goes backward in self-care, toilet use or sleep
• often has worries, fears, stomach aches or headaches linked to school or friends

Most children:

• read longer books and understand what they read
• write texts of several paragraphs, with a beginning, a middle and an end
• multiply, divide and work with fractions
• plan and finish school projects that take several days
• have one or two close friends and a wider circle of classmates
• care a lot about what friends think, and compare themselves with them
• want more independence and more privacy
• take care of a chore without a daily reminder
• understand right and wrong, and see other people’s point of view
• in some children, show the first signs of puberty. Girls usually start 1 to 2 years before boys.

Call your doctor if your child:

• keeps falling behind in reading, writing or math
• often refuses school, or has stomach aches or headaches before school
• is sad or irritable most of the day for more than 2 weeks
• talks about hopelessness, hurting themselves or wanting to die. Call the same day.
• suddenly loses interest in things they used to enjoy
• has severe worry or panic, or refuses to leave the house
• is aggressive, cruel to animals, or breaks rules again and again
• changes how they eat, avoids food, eats in binges, or loses or gains weight fast
• sleeps much less or much more than before
• has no close friends and stays alone most of the day

Most children:

• handle more schoolwork, with several teachers and subjects
• read and write for longer, and can defend an opinion in writing
• often see things in all-or-nothing terms
• care a lot about friends and fitting in, and may change friend groups
• feel self-conscious about how they look
• want more privacy and push against family rules
• take care of their hygiene, like showering, deodorant and period care
• show clear signs of puberty. Many girls get their first period around 12.
• have mood swings and stronger feelings
• use phones and messages as a main way to keep in touch with friends
• start to form their own ideas about who they are and what they believe

Call your doctor if your child:

• is sad, irritable or hopeless most of the day for more than 2 weeks
• talks about suicide, hurting themselves or wanting to die. Call the same day.
• has cuts, burns or bruises they hide or cannot explain
• loses weight suddenly, skips meals, counts calories, eats in binges or vomits on purpose
• has severe worry, panic attacks, or refuses to leave the house
• avoids school, or their grades drop
• is aggressive, makes threats, or breaks rules in ways that could bring trouble with the law
• drinks alcohol, vapes or uses drugs
• pulls away from everyone and stays alone in their room most of the day
• cannot sleep, or sleeps most of the day

Most teens:

• handle more abstract schoolwork, like algebra and science
• think about “what if” questions and about right and wrong
• have a steady group of friends, whose opinion can weigh as much as yours
• work out who they are, what they value and what they like
• want to choose their own clothes, music and friends
• are well into puberty, and many have a growth spurt
• start to have romantic and sexual feelings
• manage their own hygiene, sleep and most school tasks
• have mood swings and feel hurt easily
• spend a lot of time online, on social media, games and messages

Call your doctor if your teen:

• is sad, irritable or hopeless most of the day for more than 2 weeks
• talks about suicide, hurting themselves or wanting to die. Call the same day.
• has cuts, burns or bruises they hide or cannot explain
• loses weight suddenly, skips meals, counts calories, eats in binges or vomits on purpose
• has severe worry, panic attacks, or refuses to leave the house
• keeps refusing school, fails classes, or is expelled
• is aggressive, makes threats, or breaks rules in ways that could bring trouble with the law
• drinks alcohol, vapes, or uses cannabis or other drugs
• pulls away from everyone and stays alone in their room most of the day
• is a girl with no breast growth by 13
• is a boy with no signs of puberty by 14
• has online contact that worries you, like bullying, an adult stranger or sharing sexual images
• has sleep problems that last for weeks

Most teens:

• make plans for after school, like university or work
• think about right and wrong, politics and their future
• may have a part-time job or do volunteer work
• manage their own schedule and most daily tasks
• have steady friendships, and may be in a romantic relationship
• have a clearer sense of who they are and what they believe
• are close to their adult body. Most girls have regular periods, and many boys are still growing.
• may see the doctor alone for part of the visit, and bring their own questions
• still have strong feelings, but the swings settle compared with earlier years

Call your doctor if your teen:

• is sad, irritable or hopeless most of the day for more than 2 weeks
• talks about suicide, hurting themselves or wanting to die. Call the same day.
• has cuts, burns or bruises they hide or cannot explain
• loses weight suddenly, skips meals, counts calories, eats in binges or vomits on purpose
• has severe worry, panic attacks, or refuses to leave the house
• keeps refusing school, fails classes, or drops out
• is aggressive, makes threats, or breaks rules in ways that could bring trouble with the law
• uses alcohol or drugs in a way that affects school, work or friendships
• pulls away from everyone and stays alone in their room most of the day
• takes risks like fights, unprotected sex with several partners, or riding with a driver who has been drinking
• suddenly hears or sees things that are not there, becomes very suspicious of others, or speaks in a confused way. Call the same day.
• has unsafe contact online, or a relationship with an adult they met online
• is a girl who has not had a first period by 15
• is a boy with no signs of puberty yet

If your child loses a skill they once had, call your doctor right away. At any age, this always needs a check.

Losing a skill is a stronger warning sign than learning one slowly. It can be words, babbling, smiling, eye contact, walking or using the hands. In an older child, it can be reading, writing, toilet use or self-care.

You do not need to wait for the next visit. Help works best when it starts early.

If your child is in danger right now, for example after hurting themselves or swallowing pills, call the Red Cross on 140.

Call your doctor if you see a sign from the lists above, or if your child seems behind for their age. Call also if a nurse, a teacher or a relative raises a concern.

Your doctor checks development at each visit. Tell them what you see at home. A check can reassure you, or start help early.