11.2: Communication and Language Milestones in Infancy and Toddlerhood

Milestones

Milestones represent what most children can do by specific ages; however, it is important to remember that children do not achieve these milestones at the same exact ages—milestones only represent the average age at which they are achieved. If a child has not achieved specific milestones by a specific age, it does not necessarily suggest a delay or disability; however, there are specific ages where if certain milestones are not achieved, caregivers should encourage the child’s parents to communicate with their family pediatrician. Here is a table of common communication and language milestones for infants and toddlers.

What most children can do by age^[1]

Age	What Most Children Can Do By Each Age
2 months	Coo and make gurgling sounds Turn their head toward sounds
4 months	Begin to babble Babble with expression and copy sounds they hear Cry in different ways to show hunger, pain, or being tired
6 months	Respond to sounds by making sounds String vowels together when babbling (“ah,” “eh,” “oh”) and like taking turns with a caregiver while making sounds Respond to their own name Make sounds to show joy and displeasure Begin to say consonant sounds (jabbering with “m,” “b”)
9 months	Understand the meaning of “no” Make a lot of different sounds like “mamamama” and “bababababa” Copy the sounds and gestures of others Use their fingers to point at things
12 months	Respond to simple spoken requests Use simple gestures, like shaking their head “no” or waving “bye-bye” Make sounds with changes in tone (sounds more like speech) Say “mama” and “dada” and exclamations like “uh-oh!” Try to say words caregivers say
18 months	Say several single words Say “no” and shake their head “no” Point to show someone what they want
24 months	Point to things or pictures when they are named Know names of familiar people and body parts Say sentences with 2 to 4 words Follow simple instructions Repeat words overheard in conversation Point to things in a book
36 months	Follow instructions with 2 or 3 steps Can name most familiar things Understand words like “in,” “on,” and “under” Say their first name, age, and sex Name a friend Say words like “I,” “me,” “we,” and “you” and some plurals (cars, dogs, cats) Talk well enough for strangers to understand them most of the time Carry on a conversation using 2 to 3 sentences

Communication & Language Concerns

The above chart represents averages of when infants and toddlers achieve various communication and language milestones. What about children who do not achieve these milestones by the ages listed? While children can indeed develop different abilities at different times, too great a delay in acquiring specific milestones can be a concern. The chart below is from the Center for Disease Control and Prevention (CDC). The chart adopts a proactive stance—we should take action early when developmental concerns arise rather than the perspective of waiting to see if a child “catches up”. Again, while children do develop at their own pace, being proactive during these critical early years is essential as early recognition of delays and disabilities can lead to early intervention with the potential for greater positive outcomes (Caselli, Pyers & Lieberman, 2021; Fuller et al., 2020; Roberts & Kaiser, 2015). Caregivers should encourage parents to communicate with their family's pediatrician if children are not achieving milestones by the ages listed below. Most caregivers are not professionally trained to officially assess the developmental abilities of children; however, caregivers have the ability to track developmental progress and are often the first to notice developmental concerns.

Language Development Concerns^[1]

Age	Encourage parents to communicate with their family’s pediatrician if:
By 4 months	Child doesn’t coo or make sounds Child doesn’t smile at people
By 6 months	Child doesn’t make vowel sounds (“ah”, “eh”, “oh”) Child doesn’t respond to sounds around him Child doesn’t laugh or make squealing sounds
By 9 months	Child doesn’t babble (“mama”, “baba”, “dada”) Child doesn’t play any games involving back-and-forth play Child doesn’t respond to their own name Child doesn’t seem to recognize familiar people Child doesn’t look where you point
By 12 months	Child doesn’t say single words like “mama” or “dada” Child doesn’t learn gestures like waving or shaking head Child doesn’t point to things
By 18 months	Child doesn’t copy others Child doesn’t gain new words Child doesn’t have at least 6 words
By 24 months	Child doesn’t use 2-word phrases (for example, “drink milk”) Child doesn’t copy actions and words Child doesn’t follow simple instructions
By 36 months	Child drools or has very unclear speech Child can’t work simple toys (such as peg boards, simple puzzles, turning handle) Child doesn’t speak in sentences Child doesn’t understand simple instructions Child doesn’t play pretend or make-believe Child doesn’t want to play with other children or with toys Child doesn’t make eye contact

^[1] CDC’s Developmental Milestones by the Centers for Disease Control and Prevention is in the public domain.