How to raise a bilingual child: what actually works in the toddler years

17 October 2026 · 8 minute read

If you're raising a kid with two or three languages, you've probably collected a pile of rules by now: one parent, one language, only the minority language at home, never mix, always mix. Here's what the research says actually decides it: how much of each language your child hears and uses, and above all whether the language that's quiet outside your front door gets enough room inside it. A method your family can keep up for years beats a perfect one you drop by March.

Good news: there's no secret technique you're missing. The slightly less fun news is that who speaks what at the dinner table will shape your child's languages more than any class, app or flashcard.

Pick a plan you can actually keep up

Most families land on one of a few setups. With one parent, one language, each adult sticks to their own language, so a kid in Berlin might get German from one parent and Italian from the other. With minority language at home, everyone at home speaks the language the neighborhood doesn't, and daycare, friends and the playground handle the local one. Some families split by time or place instead, like Spanish on weekends or English at grandma's.

Researchers who review this work call one parent, one language useful, and also neither necessary nor sufficient for becoming bilingual. A Dutch study of 136 bilingual families put that to a direct test: children from one parent, one language homes, minority language homes and homes where parents mixed did look different at first, but once the researchers counted how much of each language the children actually heard, the family pattern predicted only one of four outcomes, while the amount each parent spoke predicted all four (Verhagen, Kuiken and Andringa, 2022). A review of 42 studies on family language habits lands in the same place, with what families do day to day turning up as the factor linked to children's languages far more often than the rules they set (Hollebeke and colleagues, 2020).

What nearly 1,900 families told one researcher

The clearest numbers come from a big survey by the linguist Annick De Houwer, who asked 1,899 families in Flanders, the Dutch-speaking part of Belgium, which languages the parents used at home and which ones their 6 to 10 year olds actually spoke. Every child spoke Dutch, since that's what the community speaks. Far fewer spoke the family's other language, and the setup at home made a big difference.

When both parents spoke only the minority language at home, almost every child spoke it too. When each parent stuck to a different language, about three in four did. When one parent used both languages and the other used only Dutch, it dropped to about a third. François Grosjean's summary of the study walks through each group, and the original paper concludes that one parent, one language was neither a necessary nor a sufficient condition for success.

A survey can't prove cause and effect, and families who go all in on the minority language probably differ in other ways too. Still, the direction is hard to ignore: the community language shows up on its own, and the home language needs a bodyguard.

How much is enough?

Nobody can hand you an exact number, but the research gives a sense of scale. Byers-Heinlein and Lew-Williams note that a child generally needs at least 10 to 25 percent of their exposure in a language to learn to speak it, and that both quantity and quality count. Quality means live conversation with real people, where an adult answers what the child says, names what they're looking at and takes turns. A TV droning in the background does very little.

Two numbers you may run into deserve a footnote. Toddlers can pick up early words in a language that makes up as little as 20 percent of what they hear, though clinicians reviewing that work stress it says nothing about whether the language will keep growing on that diet (Hoff and Core, 2015). And the 60 percent figure that circulates online comes from a study of 2½ year olds in England, where children who heard English at least 60 percent of the time scored like English-only peers on English tests (Cattani and colleagues, 2014). That tells you when one language looks monolingual, which is a different goal from a child who speaks both.

Who your child hears matters too. In a study of 29 two-year-olds in South Florida, toddlers who heard English from more different people had bigger English vocabularies and more grown-up grammar, even after counting how much English they heard in total (Place and Hoff, 2011). The same pattern was weaker for Spanish in that study, so treat it as a strong hint. A home language that comes from one parent alone is a thin stream, and a grandparent on video, a babysitter or another family from your community all widen it.

To check your own balance, walk through a normal week and estimate the hours your child spends in each language. If daycare is nine hours a day in the local language and the home language gets breakfast and bedtime, the local language is going to win, and that's your cue to add more.

Speak the language you speak best

Parents who moved countries still hear that they should switch to the local language to give their child a head start at school. The research points the other way. When researchers recorded 60 mothers playing with their 2½ year olds in English, mothers who had learned English late and rated it as limited talked just as much as native speakers, but their sentences were about a third shorter and they used about 40 percent fewer different words, while mothers who rated their English as good were statistically indistinguishable from native speakers (Hoff, Core and Shanks, 2019). A study of 50 preschoolers in the Netherlands found that whether a parent was a native Dutch speaker didn't predict the children's Dutch, while how fluent the non-native speakers were did (Unsworth and colleagues, 2019).

So speak the language you can tell a story in, tease in and explain thunder in, and let the local language come from fluent speakers at daycare and beyond. Being good rather than perfect at a language is fine, and a recent review warns against assuming that anything short of native proficiency makes a language unusable with your child (Byers-Heinlein, Kircher and Lew-Williams, 2025). There's more on this in our post on which language to speak to your child.

Make the home language the fun one

Kids learn the words that come attached to things they care about. If the home language is the language of songs, silly voices, bath time and picture books, a toddler has a reason to want it. If it's only the language of "put your shoes on," you can see why they'd prefer the other one.

There's data behind the warm and fuzzy part. In a study of 47 Spanish and English speaking toddlers in Chicago, how warm caregivers were during play at 18 months, together with how many different words they used, accounted for about a third of the differences in the children's vocabularies at two (Gámez and colleagues, 2022). It's a correlation from one city, but it fits everything else on this list: varied words, delivered by someone who's enjoying themselves.

Short shared moments add up: a song in the car, a picture book before sleep, a game on the sofa. That last one is why we build LingoPlaytime. The games are short, they speak the languages on your child's list in a natural-sounding voice, and they work best with a grown-up next to them, naming things and laughing along.

Mixing languages is normal

Expect your kid to mix: a German word in an English sentence, an Italian question answered in German. Researchers call this a normal part of bilingual development, a sign the child is using every word they have. More on that in our post on bilingual toddlers and late talking.

If it's your own mixing that worries you, a 2026 synthesis of seven studies covering 541 children found that parents' mixing had no relation to how well children spoke either language, and at most a negligible to small link with how well they understood the majority language (Verhoeven and colleagues, 2026). Researchers advising policymakers put it neatly: code-switching should be neither discouraged nor encouraged (Fibla and colleagues, 2021).

Keep reading

Which language should you speak to your child? Usually the one you speak best

Should you speak the local language to help your child at school? Research on parents speaking a second language, native versus fluent input, and where the community language really comes from.

Is my bilingual toddler a late talker? What the research says

Worried your bilingual toddler is talking late or mixing languages? Research shows bilingualism doesn't cause speech delays. How to count words across languages, and when to get help.