Social communication and interaction skills can be challenging for people with ASD.

Examples of social communication and social interaction characteristics related to ASD by age:

• Does not respond to name by 9 months of age.
• Does not show facial expressions like happy, sad, angry, and surprised by 9 months of age.
• Does not play simple interactive games like pat-a-cake by 12 months of age.
• Uses few or no gestures by 12 months of age (for example, does not wave goodbye).
• Does not share interests with others by 15 months of age (for example, shows you an object that they like).
• Does not point to show you something interesting by 18 months of age.
• Does not notice when others are hurt or upset by 24 months of age.
• Does not notice other children and join them in play by 36 months of age.
• Does not pretend to be something else, like a teacher or superhero, during play by 48 months of age.
• Does not sing, dance, or act for you by 60 months of age.

Most people with ASD have other related characteristics. These might include

• Delayed language skills
• Delayed movement skills
• Delayed cognitive or learning skills
• Hyperactive, impulsive, and/or inattentive behavior
• Epilepsy or seizure disorder
• Unusual eating and sleeping habits
• Gastrointestinal issues (for example, constipation)
• Unusual mood or emotional reactions
• Anxiety, stress, or excessive worry
• Lack of fear or more fear than expected

It is important to note that children with ASD may not have all or any of the behaviors listed as examples here. (Source: CDC website)