Related abilities

Is interested in interacting with others, e.g. peek-a-boo (9-12 months)

Maintains eye contact with people during playful interactions (9-12 months)

Is able to sit unsupported and turn head to look at objects without losing balance

Has grown accustomed to everyday sounds and is usually not startled by them (9-12 months)

Is generally happy when not hungry or tired (9-12 months)

Is able to enjoy a wide variety of touch, noise, and smells (9-12 months)