Child development stages describe theoretical milestones of child development. Many stage models of development have been proposed, used as working concepts and in some cases asserted as nativist theories.
This article puts forward a general model based on the most widely accepted developmental stages. However, it is important to understand that there is wide variation in terms of what is considered "normal," driven by a wide variety of genetic, cognitive, physical, family, cultural, nutritional, educational, and environmental factors. Many children will reach some or most of these milestones at different times from the norm.
Overview of motor, speech, vision and hearing development
Physical specifications
Specifications sorted by reached age
1–4 months
Physical
Head and chest circumference are nearly equal to the part of the abdomen.
Head circumference increases approximately 2 cm per month until two months, then increases 1.5 cm per month until four months.
Increases are an important indication of continued brain growth.