Every parent knows the excitement of watching your newborn grow and develop. We marvel as our little ones hopefully hit all the childhood developmental milestones as expected — and how many developmental milestones there are! Many parents wonder What are childhood developmental milestones by age? The Centers for Disease Control and Prevention, or CDC, offers a handy developmental milestone checklist that can help you track your child's progress. Be sure to refer to that for additional insight. Here, though, are the childhood developmental milestones at key ages. Take a look!

The Developmental Milestones at 2 months of Age

The first two months are chock-full of many developmental milestones. By 2 months old, babies are eating seemingly around the clock. And while they sleep a lot, they are likely not sleeping through the night just yet. They're getting stronger everyday, though. Here's what to look for in your baby when they reach 2 months old.

The Developmental Milestones at 4 months of Age

By 4 months old, your little one will become much more alert and aware of the world around them. They are likely going for longer stretches of time between feedings, and they may be finally sleeping for longer stretches as well. They are recognizing familiar faces and favorite toys, and they're generally becoming much more interactive. Here are the child developmental milestones to look for in your 4-month-old.

Your 4-month-old may be babbling and smiling, gazing at you lovingly and melting your heart when they do.

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The Developmental Milestones at 6 months of Age

By 6 months old, your little one is learning to grasp items, communicate with fun noises, and perhaps even start to eat infant cereal. They're likely sleeping around 10 hours a night (at last!), and they may be preparing to sit unassisted. Here's what to look for in the way of childhood developmental milestones in your 6-month-old.

The Developmental Milestones at 9 months of Age

You're likely marveling at all of the growth and personality your little one is expressing by this age. They are likely sitting unassisted and may even be showing signs that they're ready to crawl. You may notice your little one becomes a little more clingy when they see people they don't recognize. Keep an eye out for these key developmental milestones at 9 months of age.

The Developmental Milestones at 1 year of Age

What a major milestone you've reach when you get to celebrate your little one's first birthday! It's fascinating how much has changed in just one year. Your little one may be preparing to walk if they're not already, and they may be saying a few words like “mama,” “dada,” “baba” (for bottle) and the like. Here are the major milestones to look for when your baby turns 1 year old.

Get ready for life to get even more exciting when your little one begins walking!

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The Developmental Milestones at 15 months of Age

Your baby, now more like a toddler, has likely taken to two feet and is motoring around with ease. Life kicks into overdrive with a mobile child. They understand commands, are drinking from sippy cups and may be pointing to favorite objects or body parts. Bellybutton is always a favorite! Here are the other developmental milestones to look for in your 15-month-old.

The Developmental Milestones at 18 months of Age

By this age, your child is developing a sense of independence while making sure you're still close-by. They may be more interested in friends at this age, and their vocabulary should be expanding as they understand the names of common objects and people in their lives. What else can you expect from your 18-month-old? Here are the key developmental milestones at this age.

The Developmental Milestones at 2 Years of Age

Your independent toddler may be flexing their tantrum skills by age 2. But there's so much more magic at this age than just tantrums. Their vocabulary should hover around 50 words at this age, and they may delight in running from place to place as their agility skills progress. Here's what to look for in the way of developmental milestones at 2 years of age.

The Developmental Milestones at 30 Months of Age

At 30 months, otherwise known as 2-and-a-half years old, your little one is rapidly approaching their preschool years. From dexterity advancements to potty training, it's a most busy time. Your child should be able to color with a crayon, turn book pages and remove their clothes with little assistance. Here are the key developmental milestones to watch for at 30 months of age.

The Developmental Milestones at 3 years of Age

Your preschooler, by age 3, is likely talking up a storm, hopefully sleeping like a champ, and learning the finer points of interacting with others. Separation anxiety may be at a fever pitch, but rest assured, that's normal. If they haven't already, now's a great time to start potty training. Here are the key developmental milestones your child should reach at 3 years of age.

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