Chapter Introduction
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CHAPTER OUTLINE
Growth in Infancy
Body Size
Sleep
OPPOSING PERSPECTIVES: Where Should Babies Sleep?
Brain Development
The Senses
Motor Skills
Surviving in Good Health
Better Days Ahead
A CASE TO STUDY: Scientist at Work
Immunization
Nutrition
A VIEW FROM SCIENCE: From Breast to Formula and Back
Infant Cognition
Sensorimotor Intelligence
Information Processing
Language
The Universal Sequence
How Do They Do It?
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CHAPTER 3
The First Two Years
Body and Mind
WHAT WILL YOU KNOW?
What part of an infant grows most in the first two years?
Does immunization protect or harm babies?
If a baby doesn’t look for an object that disappears, what does that mean?
Why do people talk to babies too young to talk back?
Video: The First Two Years Body and Mind: A Brief Overview
Our first child, Bethany, was born when I was in graduate school. I studiously memorized developmental norms, including sitting at 6 months, walking and talking at 12. But at 14 months, Bethany had not yet taken her first step.
Instead of worrying, I told my husband that genes were more influential than anything we did. I had read that babies in Paris are among the latest walkers in the world, and my grandmother was French. My speculation was bolstered when our next two children, Rachel and Elissa, were also slow to walk.
The genetic hypothesis was confirmed by my students, all devoted parents. Those with ancestors from Guatemala and Ghana had infants who walked before a year, unlike those with East Asian or European heritage.
Fourteen years after Bethany, Sarah was born. I could afford a full-
I told her that Berger children walk late.
“She’ll be walking by a year,” Mrs. Todd told me. “Gillian walked at 10 months.”
“We’ll see,” I graciously replied, confident of my genetic explanation.
I underestimated Mrs. Todd. She bounced my delighted baby on her lap, day after day, and spent hours giving her “walking practice.” Sarah took her first step at 12 months, late for a Todd, early for a Berger, and a humbling lesson for me.
As a scientist, I know that a single case proves nothing. Sarah shares only half her genes with Bethany. My daughters are only one-
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