What are the child development milestones?

Alternatives to Milestones

Not all child development professionals consider milestones to be accurate measures. Many developmental psychologists, the researchers who study childhood transformation, avoid all but the motor milestones, which are generally accepted because they are less complicated and display less variance among children. Yet even physical development is not consistent: Some children may skip steps (never learning to crawl, for example), and some may exhibit a behavior once and don't repeat it consistently. A baby may roll over once, surprising herself and her parents, then not repeat it for weeks.

Grant Gutheil, a developmental psychologist at Nazareth College in Rochester, N.Y., offered an analogy to make some sense of milestones: "Milestones in child development can be seen like a car with square wheels. Each turn of the wheel is a new stage. There's a lot of struggle and waiting until the wheels turn…thunk! And, suddenly, you're in the new stage."

Child development in general is more continuous and variable, however. The car actually has round wheels; it goes forwards and backwards and may go down a blind alley. Occasionally, there's a flat tire.

According to Gutheil, there are many aspects of development that parents mistakenly assume have a linear progression, such as sharing, self-awareness and academic ability. Say, for instance, that your child won't share and is reluctant to loan her doll to her playmate or her books to her siblings. Then one day, she offers her teddy bear to a friend, and the parents celebrate. The next week, however, she smacks her younger brother for playing with her blocks. It's as if she never had the breakthrough, but that pattern can be very common in a child's development. She might try something new, experiment with it a bit, stray, and return until she's consistently exhibiting that behavior.

Child development is multi-dimensional as well, meaning that development in one area is often connected to another. Is that social smile an indication of cognitive, social or language development -- or all three? If it is all three, should they really be separate milestones?

Because many developmental psychologists ordinarily don't use milestones, they use other methods to discuss changes in development. Some options include the following:

  • Information processing: A theory that compares learning to computer processing. "Input" reaches the learner through the senses, and the information is then coded, modified and categorized. The "output" is the learner's subsequent behavior [source: Oswalt].
  • Dynamic systems: A theory proposing that learning occurs because of the ever-changing system formed by a child's intellect, body and environment [source: Smith and Thelen].
  • Overlapping waves: A theory that suggests children test multiple strategies when facing difficult problems and select the one promising the most speed and precision [source: Shrager and Siegler].

Whether or not you find the concept of milestones useful, child development is a process. Changes will occur, although not always at a pace parents might prefer.

Read on to learn more about milestones, child development and related topics.

Related HowStuffWorks Articles


  • Berk, Laura E. Infants, Children, and Adolescents. Pearson. 2008.
  • Goswami, Usha. "Cognition in Children." Psychology Press, Ltd. 1998.
  • Gutheil, Grant. Assistant professor, Nazareth College. Personal interview. February 25, 2010.
  • Jayson, Sharon. "It's Cooler than Ever to be a Tween, but Is Childhood Lost?" USA Today. February 4, 2009. (February 24, 2010.)http://www.usatoday.com/news/health/2009-02-03-tweens-behavior_N.htm
  • Oswalt, Angela. "Early Childhood Cognitive Development: Information Processing." Child Development and Parenting: Early Childhood. 2010. (February 25, 2010) http://www.bhcmhmr.org/poc/view_doc.php?type=doc&id=12760&cn=462
  • Price, Michael. "Liar, Liar, Neurons Fire." Monitor on Psychology. Vol. 93, no. 1. Page 30. January 2008. (February 25, 2010)http://www.apa.org/monitor/jan08/liar.aspx
  • Primus IV. "Good Will Sidis." Harvard Magazine. March-April 1998. (February 22, 2010). http://harvardmagazine.com/1998/03/pump.html
  • Shrager, Jeff, and Robert Seigler. "SCADS: A Model of Children's Strategy Choices and Strategy Discoveries." Psychological Science. Vol. 9, no. 5. Pages 405-410. September 1998. (February 25, 2010)http://www.psy.cmu.edu/~siegler/shragersiegler98.pdf
  • Smith, Linda B., and Esther Thelen. "Development as a Dynamic System." TRENDS in Cognitive Science. Vol. 7, no. 8. Pages 343-348. August 2003. (February 25, 2010) http://www.iub.edu/~cogdev/labwork/dynamicsystem.pdf
  • Snow, Richard F. "William James Sidis." American Heritage Magazine. Vol. 30, Issue 3. April/May 1970. (February 21, 2010). http://www.americanheritage.com/articles/magazine/ah/1979/3/1979_3_52_print.shtml
  • Wellesley Centers for Women. "Commentary: So Sexy So Soon." Research and Action Report Spring/Summer 2009.http://www.wcwonline.org/content/view/2010/198/