There is so much to love about life with your 18-month-old: From their infectious fascination with the world around them to their happy energy to their sweet snuggles and more. Your child is uniquely, wonderfully, perfectly themselves! And, by one-and-a-half years into the journey, you’ve already proven to be adaptable and resilient—which are traits that will serve you well in the coming months. 

Your 18-Month-Old’s Behavior & Emotions

Why is that? Well, “the terrible twos” often kick in well before the second birthday. Around 18 months, toddlers have tendencies to become more aggressive and demanding. Many parents who celebrated their child’s kindness and compliance just months ago are left wondering how that child was replaced by one whose favorite words are “no” and “mine.”  

But here’s the thing, children at this stage are just learning how to process big emotions. This isn’t terrible. It’s part of life. And parents have the opportunity to help their children get through toddlerhood (and beyond) with more emotional intelligence by helping them learn to acknowledge and positively manage emotions. There’s a strong argument that emotional intelligence is even more important than IQ when it comes to living a happy, successful life! Here are some tips to help build your toddler’s emotional intelligence. And while you’re at it, it’s not a bad idea to introduce books that teach empathy and kindness

Your 18-Month-Old’s Development

It’s clear your baby remembers things—that’s how they recognize you and know you by your name, right? As true as that is, they are now on the cusp of a new stage of memory: developing more explicit, long-lasting memories. No, that doesn’t mean they’ll vividly remember daily life from this time… You probably don’t remember much from before you were nearly school-aged, right?  

However, developing memory skills is a sign their cognitive abilities are becoming more complex. This affects the way they think of themselves as an independent person, how they relate to others, how they organize their thoughts, and more. In other words: Your not-so-little baby is really coming into their own.  

Still, they aren’t adults. They aren’t even miniature children. At 18 months old, they are toddlers—in their own emotionally volatile, energetic, curious category. They are trying to figure out their world. And, to be honest, it seems downright weird to them at times. You’ll see this as they try to push back (or completely ignore) rules that aren’t aligned with what they want. Aim to listen, explain, and calmly reinforce limits. 

18-Month Milestone Checklist

By 18 months, most children (75%) have hit the following developmental milestones:  

Social and Emotional Milestones

  • Moves away from you, but looks to make sure you’re nearby
  • Points to show others something interesting 
  • Puts hands out for you to wash them
  • Looks at a few pages in a book with you
  • Pushes arm through sleeve or lifts a foot to help get dressed 

Language and Communication Milestones

  • Attempts to say three or more words besides “mama” or “dada”
  • Follows a one-step command without gestures

Learning, Thinking, and Problem-Solving Milestones

  • Mimics you doing chores, such as using a broom to sweep
  • Plays with toys in a simple way, like pushing a toy car

Movement and Physical Development Milestones

  • Walks independently
  • Scribbles
  • Independently climbs on and off a sofa or chair
  • Drinks from a lid-free cup
  • Uses fingers to feed self
  • Tries to eat with a spoon 

18-Month-Old Milestones: Health, Physical Growth and Abilities

It’s common for toddlers to experience a growth spurt around 18 months. Brace yourself to size up in clothes and shoes! That physical growth calls for lots of fuel in the forms of food and sleep. You’re probably also in the habit of taking snacks when you’re out of the house, but avoid the habit of “grazing,” which can interfere with healthy meals. 

Now walking, probably running, and maybe even jumping, your toddler is getting increasingly sure on their feet. That means you have to be on your feet a lot more these days. Find some favorite activities that can meet their desire for movement while giving you a bit of a break: Think about turning on some fun tunes and watching their dance moves, signing up for a toddler gymnastics class, or toddler-proofing a yard space where they can play while you observe from a nearby seat. 

Knowing what you do about your toddler’s boundless energy, you may consider skipping the stroller on shorter outings. However, don’t be surprised if you still have to carry your toddler for some of the journey. Even when their legs might be capable, their minds might feel overstimulated by a busy environment and the stroller will suddenly seem more inviting. You know your child best, but our advice is still to bring a stroller or carrier when you anticipate walking more than half of a mile.

The 18-Month Checkup

This is your baby’s last well child visit before they turn 2! Depending on where your child is in their vaccine sequence, it might be time for doses of the HepA and/or DTap shots. Learn more about the recommended vaccine schedule

18-Month-Old Height and Weight

At 18 months, the average boy is 32.4 inches (82.3 cm) tall and weighs 24 pounds (10.9 kg). And girls tend to be around 31.8 inches (80.7 cm) tall and weigh about 22.5 pounds (10.2 kg) at 18 months.

Putting the “Play” in Playground

Spending time at the playground is a quintessential part of childhood—with developmental benefits to boot. So much more than fun and games, playgrounds can also help young children with their agility, confidence, and strength. If you’re ready to test out some playgrounds, remember that your child is still young and there are many years of fun ahead. No need to master the monkey bars yet! Here’s how to safely enjoy the playground with your toddler.

  • Scope out the playground before letting them run free. Many types of playground equipment are designed for older (even much older) kids—and you shouldn’t trust your 18-month-old to know their limits yet. Always stay close.
  • Per the Handbook for Public Playground Safety, the best equipment for young toddlers to enjoy includes bucket swings, ramps, stairs, spring rockers, and small slides. Do not go down slides with your child, as this may cause injury
  • Avoid dressing your child in hoods, unzippered jackets, necklaces, and other loose items that can get stuck. Have them wear flat shoes. 

18-Month-Old Milestones: Final Thoughts

Your growing tyke has experienced such an explosion of developmental changes already…and by the end of the month, they’ll likely be adding even more to their growing list. Just don’t forget: It’s totally normal for some toddlers to be right on target with their milestones, with others a little behind, and still more a wee bit ahead. All children are different! You’ll likely go over where your child falls on the milestone achievement checklist at your tot’s next well-visit. It’s recommended that all children be screened for general development and autism at their 18-month check-up. Ask your child’s pediatrician for more info.


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  • The Happiest Toddler on the Block, Dr. Harvey Karp, MD
  • A New Layered Model on Emotional Intelligence, Behavioral Sciences, May 2018
  • Long-term memory kicks in after age one, The Harvard Gazette, Nov 2002
  • ​​Centers for Disease Control and Prevention, Important Milestones, 18 Months
  • World Health Organization: Child Growth Standards, Length/Height for Age
  • World Health Organization: Child Growth Standards, Weight for Age
  • U.S. Consumer Product Safety Commission, Public Playground Safety Handbook, Dec 2015
  • The Mechanisms and Injuries Associated with Playground Slides in Young Children: Increased Risk of Lower Extremity Injuries with Riding on Laps, The American Academy of Pediatrics, Sep 2017

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Disclaimer: The information on our site is NOT medical advice for any specific person or condition. It is only meant as general information. If you have any medical questions and concerns about your child or yourself, please contact your health provider.