Understanding Developmental Milestones

A clear, supportive starting point for caregivers

Why Early Development Matters

The first years of a child’s life are a time of rapid growth, learning, and change. During this period, children build skills in a generally predictable order, with each new ability relying on skills that came before it.

For example, tummy time helps strengthen the neck, shoulders, and core, which support rolling, sitting, crawling, and eventually walking. A child doesn’t just wake up one day ready to walk — their body gets there through repeated movement, balance, and practice.

When early skills are supported, later skills often come more easily. When early skills are missed or rushed, children may still “get there,” but with more effort, compensation, or frustration later on.

How Skills Build on Each Other, Step-By-Step

Development works a bit like building a house: you can’t put up the walls before the foundation is solid.

Here are a few everyday examples:

  • Crawling helps children coordinate both sides of their bodies, which later supports walking, climbing, handwriting, and even reading.

  • Playing on the floor builds core strength and balance, which children need to sit upright at a desk or table.

  • Babbling and early sounds lay the groundwork for words, just like practicing letters comes before writing sentences.

When children skip or rush certain skills — such as going straight from sitting to walking without much crawling — they may still walk, but they may struggle later with balance, coordination, endurance, or fine motor tasks. Some skills are so foundational that skipping them may prevent the development of later skills.

While skipping or rushing a skill doesn’t necessarily mean something is “wrong,” it does indicate that later skills may be more difficult or impossible to acquire. Remember, early experiences matter.

What Developmental Milestones Really Mean

Developmental milestones describe skills most children can be expected to show by certain ages, such as pointing, walking, using words, or playing simple games. They are not deadlines and not diagnoses.

Instead, milestones help caregivers answer practical questions like:

  • What kinds of skills usually come next?

  • What should I notice during everyday play?

  • Is my child getting enough opportunities to practice new skills?

Milestones focus on what children can do in real-life situations, not test settings — things you can see during play, meals, bath time, or trips to the park.

Why Developmental Milestones Were Updated

In 2023, the CDC and the American Academy of Pediatrics (AAP) updated developmental milestones to make them clearer and more useful for families.

Previously, milestones often described skills that some children could do at certain ages. The updated milestones focus on skills most children (75% or more) are expected to achieve by specific ages, based on research and expert review.

This change helps caregivers:

  • Recognize when a skill is taking longer than expected

  • Feel more confident starting conversations with their pediatric healthcare providers early

  • Avoid unnecessary “wait-and-see” periods when support might be helpful

The goal was not to worry parents — it was to support earlier awareness and informed action.

Early Conversations Make a Difference

Caregivers are often the first to notice changes — or lack of changes — in how a child moves, communicates, plays, or interacts with others. For example:

  • A child who avoids floor play may have fewer chances to build strength.

  • A toddler who understands language but isn’t using words yet may benefit from extra communication support.

  • A child who struggles with balance may avoid playground activities, limiting practice.

You know your child best. Don't wait. If your child is not meeting one or more milestones, has lost skills he or she once had, or you have other concerns, act early. Noticing and sharing these observations early opens doors — to monitoring, screening, resources, or reassurance — without assuming anything is wrong.

If you or the doctor are still concerned:

  • Ask for a referral to a specialist who can evaluate your child further; and

  • Call your state or territory's early intervention program to find out if your child can get services to help.

Early conversations support growth. They don’t label children.

What You’ll Find Within Each Age Section

Each age-based milestone section is designed to help you connect information to everyday life. You’ll find:

  • Milestones organized by developmental area (movement, thinking, communication, and social-emotional skills)

  • Real-life examples of what skills may look like

  • Printable tools to help you observe and track development

  • Parenting Activities to help encourage and support your child’s development

You can explore in order or jump to what matters most right now.

Test Your Knowledge

A quick check — or a fast refresher if you’re short on time

1. Early Development - Why are the early years in life important for development?

  • A. Skills develop randomly

  • B. Early skills support later skills like learning and participation

  • C. Development only matters once children start school

  • B. Early skills support later skills like learning and participation

2. Understanding Milestones - What do developmental milestones represent?

  • A. Exact deadlines all children must meet

  • B. Skills most children can be expected to show by certain ages

  • C. Diagnoses used to label delays

  • B. Skills most children can be expected to show by certain ages

5. Updated Milestones (CDC & AAP) - Why do updated milestones focus on skills most children can do by certain ages?

  • A. To pressure children to perform

  • B. To clarify expectations and support earlier conversations

  • C. To compare children to each other

  • B. To clarify expectations and support earlier conversations

6. When Skills Aren’t Emerging Yet - If a child is not yet showing a skill listed for their age, what is the best next step?

  • A. Wait and see indefinitely

  • B. Compare them to other children

  • C. Share observations and concerns with pediatric professionals to consider next steps, as early as possible

  • C. Share observations and concerns with pediatric professionals to consider next steps, as early as possible

3. How Skills Build - Why is tummy time important for later skills like sitting and walking?

  • A. It keeps babies busy

  • B. It strengthens the muscles needed for future movement

  • C. It replaces the need for crawling

  • B. It strengthens the muscles needed for future movement

4. Skipping Skills - What can happen when children skip or rush early developmental skills?

  • A. They always catch up with no effects

  • B. They may develop later skills with more effort or difficulty, and in some cases, may not be able to develop them

  • C. It means something is wrong

  • B. They may develop later skills with more effort or difficulty

7. Caregiver Role - Why are caregivers especially important in noticing development?

  • A. They see children in everyday, natural settings

  • B. They perform formal assessments

  • C. They replace healthcare providers

  • A. They see children in everyday, natural settings

8. Using the Age Sections - What can caregivers expect to find in each age-specific section?

  • A. Medical diagnoses

  • B. Milestones organized by developmental area, printable tools, and real-life examples

  • C. Parenting rules

  • B. Milestones organized by developmental area, printable tools, and real-life examples

Back to the Milestone Moments Education Hub

Please note that…

This information is intended to support learning and awareness, not to replace guidance from a healthcare or early childhood professional.