How many words should your toddler know?

At 20 months, my daughter Peyton's favourite word is “no.” In fact, “no” is one of the small handful of words she’s actually mastered. If the Canadian Association of speech-Language Pathologists and Audiologists is right, my not-so Chatty Cathy has only four months to learn the 200 words that are supposed to make up her vocabulary by the time she’s two. If you’re worried that your child’s verbal development isn’t up to par, take heart: According to Melanie Soderstrom, director of the Baby Language Lab and associate professor at the University of Manitoba in Winnipeg, there’s no concrete answer to the number of words little ones should know by toddlerhood.

Typical first words Some children tend to focus on social words, like “bye-bye” or “thank you,” while others focus on labelling objects, like “car” or “doll.” Sara Turner, a registered speech-language pathologist in Calgary, says the most common words kids learn first are: “mommy” and “daddy,” names of siblings and/or pets, favourite foods and favourite toys. Partial words also count. At our house, when Peyton screams for “wa,” we know she wants water. “Awo” is an arrowroot cookie. “Kids may not say the word exactly as an adult would, but you can count it as a word as long as they say it consistently in the right context,” Soderstrom says.

Read more: My chatty toddler>

Being a late bloomer is OK Kathryn Dickson’s daughter Maeve, now three, didn’t really start talking until she was almost 30 months old. “After her hearing tested as fine, we freaked out,” says Dickson. “We had meetings at her Montessori school, and with her paediatrician. But then, one day, the words just started to flow into sentences, and that was the end of that.”

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Birth order can Make a difference younger siblings may have less need to communicate, Turner says. “When the older sibling asks for a snack, for example, the younger one gets a snack, too, without having to ask.” First-born children may also receive more one-on-one time for conversation with adults. “The extra undivided attention can give them an advantage,” Turner says. And sometimes — like in our family — because our eldest child never pipes down, her little sister can’t get a word in edgewise.

A version of this article appeared in our September 2012 issue with the headline “Look who's talking,” pp. 84.