Hi there Sydney and thanks for the great question. You’ve actually raise two terrific issues we can explore here on the One Sassy Doctor blog: one about comparing the development of twins and the other about what a 20 month old’s traditional speech and language development would be.
Actually, many parents of similar-aged siblings or twins wonder when there is variation in developmental progress. As a mom of two sets of twins, I totally understand that it’s nearly impossible not to compare & worry when one twin progresses to a stage that the other hasn’t yet hit. As with all children, we know as parents that it’s best to try and refrain from comparisons. Here we’ll address why::
Developmental stages vary between children. In fact, the word “normal” or “expected” developmental stage refers to a wide range of months; with the outliers (children who do not progress until well after an age range that depends on the specific task) reflecting the need for early interventional assessments. Factors such as prematurity influence development, as do personality traits (your chatterbox will probably always be a chatterbox!). Interesting in twins, one having progressed language developmental may actually be an expression of their twin relationship – with the chatterbox taking over the communication for the two of them!
Between 18 and 21 months, toddlers will traditionally begin to imitate the words they hear and have a spoken vocabulary of about 12-15 words. Even if there are no two word sentences being uttered yet, babies at this age may understand simple phrases. In your question, you mention that one of your children have no understandable words at all by 20 months and this is something you should talk to your pediatrician about. Your doctor potentially would refer you to a hearing test as a first step. A 20 month old, twin or no twin, would be expected to have some vocabulary—and this is something that can be evaluated further in a formal process called Early Intervention (EI). Actually, our next post is in response to a mom who asked about EI so please keep following our posts. Thanks, Sydney!
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