Social and Emotional Development

By 9 months, most children:

• Socialize with preferred adults by reciprocally smiling, laughing, or vocalizing
• “Converse” with familiar adults by imitating or making faces at adults who make faces at them
• Relax when picked up and held by a familiar adult
• Search for an adult caregiver who might be out of sight
• Engage in turn-taking interactions, such as peek-a-boo
• Repeat actions that elicit social responses from others

By 18 months, most children:

• Imitate adult behavior by repeating and practicing through play (e.g., sweeping with a toy broom, “talking” on a cell phone)
• Use gestures, body language, and/or vocalizations to seek out help from a preferred adult
•  Participate in back-and-forth games with adults
• Seek comfort from a preferred adult when tired or hungry
• Expand their exploration of their environment in the presence of trusted adults, and regularly check in (visually or physically) with these adults when experiencing stress or uncertainty

By 24 months, most children:

• Imitate by continuing to repeat actions they have seen long after they have seen them
• Initiate play and interactions with familiar adults (e.g., pretending to drive a car or bake a cake)
• Interact with adults to meet needs and wants, communicating through gestures, facial expressions, and simple words
• Continue to seek out the primary adults in their life as their secure base (using simple words as well as regular visual or physical contact) while playing or exploring the environment and when uncertain

By 36 months, most children:

• Seek adult assistance when challenged
• Demonstrate affection for familiar adults
• Seek comfort from an adult after falling down or getting hurt
• Interact with adults to solve problems or communicate about experiences or ideas

By 48 months, most children:

• Seek approval from adults
• Separate from trusted adults with minimal distress when in familiar settings or with familiar and trusted adults

By 60 months, most children:

• Maintain well-being while apart from parents or primary caretakers when in familiar settings or with familiar and trusted adults
• Have a close relationship with a consistent non-parental caregiver, showing interest in the adult’s feelings, preferences, and well-being and sharing their experiences
• Participate in longer and more reciprocal interactions (when interacting with familiar adults in role play, games, or structured activities) and take greater initiative in social interaction (including turn-taking)