By 6 months

  • Responds to changes in others' tone of voice
  • Moves eyes towards noises
  • Produces different cries for varying needs (i.e. wet diaper versus hungry)
  • Babbles speech-like sounds, such as "ba", "pa", "mi"

By 1 year

  • Turns head and looks in the direction of noises heard
  • Responds when name is called
  • Recognizes the words for familiar objects and people 
  • Responds to simple commands (i.e. "no", "come here")
  • Engages in turn-taking activity (such as "peekaboo")
  • Uses gestures for a function (i.e. waving, shaking head "yes"/"no", raising hands to be picked up)
  • Says 1-2 words at a time ("mama", "dada", "hi"). Words may not be fully intelligible.

By 2 years

  • Points to body parts
  • Follows simple 1-step directions (i.e. "throw the ball")
  • Points to pictures in books when named
  • Begins to name pictures 
  • Puts 2 words together (i.e. "Mommy up", "More juice")
  • Uses the sounds /p, b, m, h, w/ in words