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Infants (0-12 months)

Key Milestones for Each Domain

Printable Detail Sheet (PDF - Need Acrobat Reader?)

Physical

Infancy is a period of rapid physical development with responses going primarily from reflexive to more organized. Movement and physical development proceed from head control to mobility. Gradually, the infant gains control over his or her body, starting with the head. Crawling starts by 9 months and first steps are typically taken around 12 months. During this first year, the infant gradually moves into self-feeding and holding a cup.

Cognitive / Language

Infants start to vocalize, starting with crying of course, moving to babbling, cooing, and squealing. An infant will smile and laugh particularly in response to a caregiver or other favorite people. Language just begins and an infant can say “mama” and “dada” and can respond to his or her own name. Also, infants learn to understand cause and effect.

Psychosocial

This phase is characterized by the infant building a sense of safety, security, and trust in parents or other caregivers. The infant distinguishes his caregiver and will smile and use vocalizations to interact socially. Around 8 months, stranger anxiety begins and the infant may cry or frown around a stranger. Most importantly, infants develop a sense of whether the world can be trusted.