Timeline of Developmental Milestones

By Ashley.Johnson4
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    Birth through 3 Months

    Babies can recognize their caregiver's voice, quiets, if crying, and will sometimes smile in response.
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    4 to 6 Months

    Babies respond to changes in spoken tone and can vocalize when excited or displeased. Babbling produces more speech-like sounds.
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    7 to 12 Months

    Can understand and respond to simple requests and recognizes common words. Gesture is used as primary form of communication, and their first meaningful word is spoken around 12 months.
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    1 to 2 Years

    Can identify items, like pictures in books and body parts, upon request. Toddlers can follow simple commands and understand questions. They also start putting words together and asking short questions.
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    2 Years

    Toddlers engage in conversation with a MLU, or mean length of utterance, totaling to about 1.6-2.2 morphemes per utterance.
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    2 to 3 Years

    Toddlers can understand opposing terms, has words for most items, and asks for identification of novel items. They can also understand and complete 2-step tasks. MLU increases to 3.0-3.3.
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    3 to 4 Years

    Starts to understand identifying terms for colors, shapes and familial relations. They can talk about happenings from their school day or friend's homes. Use of pronouns, rhymes and plurals start. MLU is now up between 3.6 and 4.7.
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    4 to 5 Years

    Preschoolers can understand words indicating sequence of events and can understand multi-step instructions. They can repeat sentences upon request. They can identify letters and numbers. They tell stories and communicate with sentences containing two or more verbs.
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    6 to 12 Years (School Aged)

    School aged children start learning how to read and write and obtain a better grasp on grammatical structure through the help of language classes.
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    12 to 18 Years (Adolescence)

    Preteens and teenagers start using their own idiolects (individual way of speaking) and utilizing gender styles. They can tell narrations and utilize figurative language. They have a continually advancing grasp on grammatical structure.