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Lifespan Development

What Does Psychology Say?

Lifespan DevelopmentWhat Does Psychology Say?
Figure 3.1 Children undergo drastic changes during the period from infancy to toddlerhood. While these three sets of infant and toddler siblings share similar genetics and environments, differences in their development demonstrate the interplay between nature and nurture. (credit left: “Smiling toddler and newborn” by Joanne Lee/Flickr, CC BY 4.0; credit middle: “Children in leaves” by Kerry Ceszyk/Flickr, CC BY 4.0; credit right: “Cuddling siblings” by Shannon Lowey/Flickr, CC BY 4.0)

Chapter Outline

What Does Psychology Say?

At a play date with other parents and their young children, Ayah’s mother Sabah is excitedly relating the changes she has recently seen in her six-month-old daughter. “All of a sudden, she can sit on her own, and she’s trying so hard to crawl. She grabs anything within reach and says ‘ba-ba-ba’ whenever she sees my face. I can’t wait to see what she does next.” Later in the day, after her afternoon nap, Ayah explores a new toy by turning it over and over in her hands. When she drops it on the tray of her high chair, the toy lights up and begins to play music. Ayah laughs in delight and spends the next few minutes excitedly trying to get the toy to turn on again.

Ayah also has a two-year-old brother, Ben, who loves showing off “his baby” to friends and family. Sabah encourages him to help with Ayah’s care by bringing diapers when Ayah needs to be changed and by including him when she reads stories to Ayah as part of their bedtime routine. Sabah has noted that despite many similarities in the way Ayah is developing and the way Ben developed at the same age, there are also differences. For example, Ben was already crawling at six months of age but hadn’t yet started to babble. Like many parents, Sabah wonders:

  • What are the next motor milestones that Ayah will reach?
  • When might Ayah say her first word?
  • Is Ayah showing typical exploratory skills for her age?
  • Are the individual differences Sabah is observing between her two children typical?

In this chapter, you’ll consider these questions and others related to the expansive developments in physical growth and ability during this stage, including the way children learn through the use of sensory skills and memory, and the way language develops.

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