Development & Milestones

Learn about key milestones in your baby's first year to help him grow into a strong, healthy, and happy toddler.

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5 Weeks

6 Weeks

7 Weeks

2 Months

3 Months

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7 Months

8 Months

9 Months

10 Months

11 Months

12 Months

Behavioral Milestones

Understand your little one's key developments in social, emotional, and communication skills during his first year.

A newborn lying on a blanket with his arms extended after being startled.

Development & Milestones

The Newborn Startle or Moro Reflex: Causes, Tests, and Timeline

Medically Reviewed by: Rhys Brooks, MD, FAAP

A mother sitting on the floor and telling her baby "no."

Development & Milestones

When Do Babies Understand What “No” Means?

Medically Reviewed by: Mary Olson, DO

A father holding his little girl while her mother encourages her to talk.

Development & Milestones

When Do Babies Start Talking? Speech Milestones to Watch Out For

Medically Reviewed by: Rhys Brooks, MD, FAAP

Baby crying in his crib as a result of separation anxiety.

Development & Milestones

Separation Anxiety in Babies: Tips for Night and Day

Medically Reviewed by: Rhys Brooks, MD, FAAP

Development & Milestones

When Do Babies Start Laughing and Smiling?

Medically Reviewed by: Rhys Brooks, MD, FAAP

Baby babbling and smiling up at his mom.

Development & Milestones

When Do Babies Usually Start Babbling?

Medically Reviewed by: Rhys Brooks, MD, FAAP

Crying

Learn why your baby cries, what it can mean, and how to soothe him effectively.

Development & Milestones

Everything You Need to Know About PURPLE Crying in Babies

Medically Reviewed by: Rhys Brooks, MD, FAAP

Baby girl lying down and crying during the "witching hour."

Development & Milestones

Decoding the Baby “Witching Hour”: What’s Behind the Evening Fuss?

Medically Reviewed by: Mary Olson, DO

Newborn Health

Receive expert guidance on how to care for your baby and when to seek medical advice during those early days.

A young baby lying on her stomach, symbolizing the age when babies become less vulnerable to sudden infant death syndrome.

Development & Milestones

Sudden Infant Death Syndrome (SIDS): Risks and Prevention

Medically Reviewed by: Rhys Brooks, MD, FAAP

Physical Milestones

Explore the exciting physical milestones your baby may reach in his first year, such as rolling over, sitting up, crawling, and even walking.

Development & Milestones

When Is It Safe for Your Baby to Go on Swings?

Medically Reviewed by: Rhys Brooks, MD, FAAP

Close view of a newborn baby stretching his arms out, showing some of his developing bones.

Development & Milestones

How Many Bones Does Your Baby Have?

Medically Reviewed by: Mary Olson, DO

Close-up of a smiling baby boy's face after he's started teething.

Development & Milestones

When Do Babies Start Teething and How Can You Help?

Medically Reviewed by: Mary Olson, DO

Development & Milestones

When Do Babies’ Eyes Change Color?

Medically Reviewed by: Mary Olson, DO

Potty Training

Find out how to identify signs of readiness and the best ways to approach potty training for a smooth experience.

Toddler sitting on the potty, holding up a ply of toilet paper with a roll tossed on the floor next to him.

Development & Milestones

17 Signs Your Toddler Is Ready for Potty Training

Medically Reviewed by: Mary Olson, DO

Toddler standing on rug and tugging down down his pull-up diaper.

Development & Milestones

What Should You Do if Your Toddler Refuses to Potty Train?

Medically Reviewed by: Mary Olson, DO

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Development & Milestones