Introduction to All that Development and Language Practice Test

Motor development milestones like sitting, crawling, and walking usually follow a fairly consistent sequence. This progression is mainly shaped by maturation—the development of the nervous system and muscles—so the order tends to be predictable. While a supportive environment and practice can influence when a child reaches each milestone, they generally do not alter the order itself. That’s why describing the milestones as following a fixed sequence largely determined by maturation, with little effect from experience is the best fit. The idea that development is entirely experience-based, random, or unpredictable doesn’t match what’s typically observed in infancy and toddler years.