As the parent or caregiver of a child with autism, it can be helpful to become familiar with developmental milestones of babies, toddlers and young children. These milestones can help you better understand your child’s strengths and challenges, as well as specific areas for improvement. They can also help you see which parts of your child’s development might be attributed to their autism diagnosis.

The U.S. Centers for Disease Control and Prevention (CDC) Learn the Signs. Act Early. campaign includes full lists of developmental milestones by age. Some of those lists are excerpted below. The CDC defines developmental milestones as “things most children can do by a certain age.” For a more comprehensive list, visit cdc.gov/actearly.

By 6 months

  • Knows familiar faces and begins to know if someone is a stranger
  • Likes to play with others, especially parents
  • Responds to other people's emotions and often seems happy
  • Responds to sounds by making sounds
  • Strings vowels together when babbling ("ah," "eh," "oh")
  • Makes sounds to show joy and displeasure
  • Begins to say consonant sounds (jabbering with "m," "b")

By 1 year

  • Is shy or nervous with strangers
  • Cries when parent or caregiver leaves
  • Has favorite things and people
  • Shows fear in some situations
  • Repeats sounds or actions to get attention
  • Plays games such as “peek-a-boo” and “pat-a-cake”
  • Responds to simple spoken requests
  • Uses simple gestures, like shaking head “no” or waving “bye-bye”
  • Says “mama” and “dada” and exclamations like “uh-oh!”

By 2 years

  • Copies adults and friends
  • Shows affection for friends without prompting
  • Understands the idea of “mine” and “his” or “hers”
  • Shows a wide range of emotions
  • May get upset with major changes in routine
  • Follows instructions with two or three steps
  • Can name most familiar things
  • Understands words like “in,” “on,” and “under”
  • Says first name, age, and sex
  • Names a friend
  • Says words like “I,” “me,” “we,” and “you” and some plurals (cars, dogs, cats)

By 3 years

  • Copies others, especially adults and older children
  • Gets excited when with other children
  • Shows more and more independence
  • Plays mainly beside other children, but is beginning to include other children, such as in chase games
  • Says sentences with two to four words
  • Follows simple instructions
  • Plays simple make-believe games

By 4 years

  • Enjoys doing new things
  • Is more and more creative with make-believe play
  • Would rather play with other children than by himself
  • Cooperates with other children
  • Often can’t tell what’s real and what’s make-believe
  • Talks about what she likes and what she is interested in
  • Sings a song or says a poem from memory such as the “Itsy Bitsy Spider” or the “Wheels on the Bus”
  • Tells stories
  • Can say first and last name
  • Remembers parts of a story

By 5 years

  • Wants to please friends
  • Wants to be like friends
  • More likely to agree with rules
  • Likes to sing, dance, and act
  • Can tell what’s real and what’s make-believe
  • Speaks very clearly
  • Shows more independence (for example, may visit a next-door neighbor by himself [adult supervision is still needed])
  • Is sometimes demanding and sometimes very cooperative
  • Tells a simple story using full sentences