Your toddler at 12 to 18 months: development, milestones and what to expect

12 to 18 months · Development · Updated July 2026 · All articles

Somewhere in the 12 to 18 month window, your baby becomes a toddler. The change happens gradually and then all at once: the wobbly first steps across the kitchen floor, the finger raised to point at a passing bus, the little personality that is unmistakably, entirely theirs. This is one of the most dazzling stretches of early childhood, and it moves fast.

It can also feel uncertain. Walking milestones differ to what you may have expected. Language can seem to stall. Tantrums arrive. Separation anxiety peaks. Sleep shifts. None of this means anything is wrong, and almost all of it passes.

This guide covers every area of development across these six months, drawing on the American Academy of Pediatrics (AAP) 2022 milestone guidelines, the NHS, the CDC and the Royal College of Paediatrics and Child Health (RCPCH). Milestones describe what most toddlers are doing at a given age; development happens across a range, and earlier or later is usually fine. Dip in wherever you need reassurance.

Moving and physical development

Movement is one of the most visible areas of change in this period, and also one of the most variable. The range of normal is genuinely wide.

Walking: what the AAP 2022 guidelines say

A common misconception is that babies should be walking by 12 months. The AAP's updated 2022 milestone guidelines specifically moved walking to 15 months as the age by which independent walking is expected. This reflects how typical development actually looks across a broad population. Many completely healthy toddlers take their first independent steps at 13, 14 or 15 months.

Before and alongside independent walking, you are likely to see:

Once walking begins, it improves quickly. By 15 to 18 months, most toddlers are walking with some confidence. You may also begin to see early climbing onto low furniture, squatting and standing back up, and that overhand throw that is really more of an enthusiastic fling.

When to mention it to your health visitor or doctor

Fine motor skills: hands and fingers

Alongside those big gross motor developments, fine motor skills are quietly becoming more precise. The pincer grip (picking up small objects between thumb and forefinger) is well established by 12 months and becomes increasingly deliberate. You will also see:

All of this is building the hand-eye coordination and finger control that will underpin drawing, writing and self-care skills in the years ahead. The mess at mealtimes is part of the learning.

Language and communication

Language in this period can feel patchy. Some days your toddler seems to have a new word; the next they appear to have forgotten it. One toddler at 14 months has ten words; another has two. Both are within the normal range. What matters more than raw word count is the direction of travel, and the presence of intentional communication in any form.

AAP 2022 language milestones

The AAP 2022 guidelines set the following as expected:

Note that many toddlers say far more than these numbers. These are floors, not ceilings. A toddler saying 20 words at 15 months is doing well. A toddler saying two words at 15 months is worth monitoring. A toddler saying one word at 18 months is worth raising with your health visitor.

Pointing and gestures

Language is not only spoken. Pointing is one of the most significant communication milestones of this period. There are two kinds:

Proto-declarative pointing, sharing something interesting with you rather than just requesting it, usually appears around 12 to 14 months and is a meaningful sign of social communication developing. Your toddler understands that you have a shared attention and a shared experience. This is a big cognitive and social step.

Waving bye-bye also typically appears around 12 months. These non-verbal communication skills matter just as much as spoken words at this stage.

Red flags to raise at 12 months

The AAP 2022 guidelines flag the following as worth discussing with a doctor or health visitor:

Finding these does not mean something is definitely wrong, but it is always worth raising early. Early support for communication delays, when needed, makes a real difference.

Social and emotional development

Your toddler is becoming a full person with feelings, preferences and a strong sense of who they are. The 12 to 18 month window is one of the most emotionally intense in early childhood, and also one of the most rewarding to watch.

Stranger and separation anxiety

Both stranger anxiety and separation anxiety often peak in this window. This is not regression; it is a sign of cognitive progress. Your toddler has now fully grasped object permanence: people and things continue to exist when they cannot see them. Which also means that when you leave the room, they know you have genuinely gone somewhere, and they do not yet know when you are coming back.

Short, warm, consistent goodbyes tend to help more than lingering or sneaking out. Your toddler learns faster that you will come back when the goodbye is predictable. Separation anxiety usually softens through the second year, though it may peak again around any new transition.

Showing affection

Most toddlers in this period actively show affection. The enthusiastic full-body hug, the open-mouthed kiss, climbing into your lap just to be there. They also begin to show early empathy, bringing a toy to a crying friend, patting someone who seems upset, looking concerned when something unexpected happens. These are signs of social and emotional development taking root.

Preferences and individuality

By 12 to 18 months your toddler is firmly an individual with strong opinions. A favourite toy, a preferred song, a decided view about which cup is acceptable and which is not. These preferences are healthy and worth acknowledging. "You really wanted the red cup" is a small thing, but it signals that you see them.

The beginning of tantrums

Tantrums begin in this period and often intensify from around 18 months. At this age, toddlers have genuinely big emotions and very little capacity to regulate them or communicate what they need. A tantrum is not bad behaviour; it is what happens when a small person is overwhelmed by a feeling they cannot yet name or manage.

Staying calm yourself, keeping them safe and waiting it out is usually the most effective response. Reasoning during the peak of a tantrum rarely works because the thinking part of your toddler's brain is temporarily offline. Reconnecting warmly afterwards matters more than addressing the behaviour in the moment. Tantrums typically peak between 18 months and three years, then ease as language develops.

Cognitive development: how your toddler thinks

The 12 to 18 month period brings rapid cognitive growth, much of it invisible in daily life but showing up in how your toddler plays, explores and communicates.

Object permanence is now solid

Earlier in babyhood, a hidden toy was a forgotten toy. By 12 months, object permanence is fully in place. Your toddler knows that things and people continue to exist when out of sight, which is why peek-a-boo delights them and why separation feels real. It also means that searching for a hidden toy is satisfying, not confusing.

Understanding "no"

Most toddlers begin to understand the word "no" somewhere between 12 and 15 months. Reliably following it is, of course, another matter. Using "no" selectively (save it for safety situations) and redirecting to what they can do tends to work better at this age than lengthy explanations. Their understanding is real; their ability to act on it is still developing.

Early make-believe play

One of the most delightful cognitive developments of this window is the very beginning of pretend play. By 15 to 18 months you may see your toddler "feeding" a doll, holding a toy phone to their ear, or pretending to drink from an empty cup. This symbolic thinking, understanding that one object can stand in for another, is a significant step. It is also a stepping stone to language, creativity and abstract reasoning.

Pointing to share, not just to request

As mentioned in the language section, the emergence of proto-declarative pointing around 12 to 14 months shows that your toddler is grasping social communication at a deeper level. They are not just using pointing as a tool to get things. They want to share their experience of the world with you. This is a meaningful cognitive and social milestone.

The 12-month health check

The first birthday brings not just cake but an important developmental review. In the UK and other countries, this is the first formal check after the newborn period where development is comprehensively assessed.

In the UK: the 1-year review

In the UK, the 1-year health review is usually carried out by your health visitor, typically between 9 and 12 months (exact timing varies by area). At this appointment, your health visitor will typically:

Write your questions down before you go. It is very easy to walk in with three concerns and walk out having forgotten two of them. Health visitors are there to help with everything. Nothing is too small to mention.

In the US: the 12-month well-child visit

In the US, the 12-month well-child visit with your paediatrician covers similar ground: growth measurements, developmental review and vaccines. Vaccinations typically given at or around 12 months in the US include the Hib, PCV13, MMR and chickenpox vaccines, plus the hepatitis A series begins. Your paediatrician will advise on your child's specific schedule.

In Australia, the Maternal and Child Health service offers a formal check at 12 months covering development, growth, feeding and immunisations.

Sleep

Sleep in the 12 to 18 month window often surprises parents. Just when you thought the worst was behind you, another transition arrives.

How much sleep is typical

Most toddlers in this period need 11 to 14 hours of total sleep across a 24-hour period. The AAP and NHS both cite this range. This typically includes a nighttime block of around 10 to 12 hours and one or two daytime naps.

The nap transition

Most babies begin this period on two naps a day. The transition to one nap usually happens between 15 and 18 months, though some toddlers do it earlier and others take a little longer. Signs that the transition may be coming include:

The transition itself can be bumpy. For a few weeks, your toddler may seem overtired in the afternoon but resist the nap, or take a very short nap and then be difficult until bedtime. A slightly earlier bedtime during this transition often helps. The shift usually settles within four to six weeks.

Night waking

Not all toddlers sleep through the night by 12 to 18 months, and this is normal. Night waking often increases during developmental leaps, when new teeth are coming through, during illness, or after changes to routine. It tends to settle once the disruption passes.

If night waking is happening very frequently and the whole family is struggling, your health visitor can offer non-judgemental, practical support. There is no single right approach to toddler sleep.

Feeding

The transition from baby food to family food happens steadily through this period, and by 12 to 18 months most toddlers can eat broadly what everyone else is eating.

The move to family foods

There is no need for separate "toddler food" unless you choose it. By 12 months, most toddlers can eat the same meals as the rest of the family, with a few important exceptions. They will likely still need softer textures for some foods, and their portions are small, but the variety can match yours.

Foods to know about

Cow's milk as the main drink

From 12 months, full-fat cow's milk can become the main drink alongside water. The NHS recommends around 300 to 400 ml per day for toddlers, spread across drinks and dairy foods like cheese and yoghurt. This is a guideline, not a target to hit exactly. Breastfeeding or formula feeding can continue alongside or instead if you choose to.

Iron matters

Iron deficiency is one of the most common nutritional issues in toddlers, particularly where cow's milk becomes the dominant food. Good sources of iron include red meat, poultry, fish, lentils, beans, eggs, dark leafy greens and fortified breakfast cereals. Eating a source of vitamin C (such as tomatoes, peppers, citrus fruit or broccoli) alongside iron-rich plant foods helps the body absorb the iron more effectively.

Variable appetite and food refusal

Toddler appetite is notoriously unpredictable. A child who ate enthusiastically at 10 months may become extremely picky by 15 to 18 months. Neophobia (refusal to try or even touch new foods) often intensifies around 18 months. This is a normal developmental phase. Continuing to offer variety without pressure, eating together as a family, and keeping mealtimes as relaxed as possible tends to work better in the long run than cajoling, hiding vegetables or making mealtimes a battle.

Play ideas for 12 to 18 months

Play at this age is not a nice extra; it is how your toddler learns everything. The best play is usually simple, open-ended and, at least some of the time, involves you. Here are activities well-suited to this developmental stage.

On screen time: the AAP recommends avoiding screens for children under 18 months, other than video calls, and limiting use to one hour per day of high-quality content watched with a parent for children 18 to 24 months. The research concern is around passive screen time replacing interaction and play, not occasional or co-viewed use. Many families do not follow this guideline exactly, and this is context to be aware of rather than a reason for guilt.

When to talk to your health visitor or doctor

Most differences in developmental timing are nothing to worry about. That said, it is always worth getting a professional view if you notice any of the following. Health visitors and paediatricians would always rather hear a concern and offer reassurance than miss something that could benefit from early support.

At 12 months, mention it if your toddler

At 15 months, mention it if your toddler

At 18 months, mention it if your toddler

At any age: if something feels off, trust your instincts and raise it. You know your toddler better than anyone. There is no such thing as a silly concern at a health visitor appointment.

Frequently asked questions

Is my 14-month-old behind if they are not walking yet?

Not necessarily. The AAP 2022 guidelines confirm that walking independently is expected by 15 months, not 12 months. Many completely healthy toddlers take their first independent steps at 13, 14 or 15 months. If your toddler is pulling up and cruising along furniture, those are encouraging signs. Mention it at your next health visitor appointment if they are not walking by 15 months, or sooner if they are not pulling up to stand at all.

How many words should a 12-month-old say?

The AAP 2022 milestone for 12 months is at least one word besides mama and dada. By 15 months, three or more words, and by 18 months, six or more words. Gestures like waving and pointing count too. If your 12-month-old is not babbling, not responding to their name, or not using any gestures, it is worth raising with your health visitor sooner rather than waiting.

When do toddler tantrums start?

Tantrums can begin from around 12 months but typically intensify from about 18 months into the second year. They are a sign that your toddler has feelings they cannot yet regulate or communicate. Staying calm, keeping them safe and waiting it out is usually the most effective response. Tantrums tend to ease significantly once language develops enough for your toddler to say what they mean.

What should a 15-month-old eat?

By 15 months, most toddlers can eat broadly what the family eats. Offer protein (meat, fish, eggs, lentils), vegetables, fruit, dairy and starchy foods. Around 300 to 400 ml of full-fat cow's milk per day as a main drink, alongside water. Avoid honey under 12 months, whole nuts under five years, and go easy on added salt. Iron-rich foods are especially important at this age, as toddlers frequently run low on iron.

When do toddlers drop to one nap?

Most toddlers transition from two naps to one between 15 and 18 months. Signs the change is coming include refusing the morning nap, taking a very long time to fall asleep, or night sleep becoming disrupted. The transition can take a few weeks and may be bumpy. A slightly earlier bedtime during this period often helps. Some children make the transition earlier; some take a little longer. Both are fine.

What does the 12-month check involve?

In the UK, the 1-year review is carried out by your health visitor, usually around 9 to 12 months (timing varies by area). It covers growth and weight, developmental review across movement, communication and social skills, and vaccinations (MMR, Men B booster and PCV in England). Your health visitor will also ask about sleep, feeding and your own wellbeing. In the US, the 12-month well-child visit with your paediatrician follows a similar format, with vaccines including Hib, PCV13, MMR, chickenpox and the start of the hepatitis A series.

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