Which language should you speak to your child at home?

“Which language should we speak to our child at home?”

The question comes up often in international families. One parent speaks French, the other English. The family lives in Spain. The child will soon start at a bilingual school. The grandparents speak yet another language.

And sometimes a very tempting idea follows: since our child needs to succeed in several languages, we might as well speak whichever language will be most useful to them.

This is exactly where it pays to slow down.

When a parent gives up a language they master perfectly to speak one they master less well, they do not just change the vocabulary used at home. They may also change how rich their conversations with their child can be.

And that matters far more than it seems.

A child’s first language is not a school subject

When parents speak to their child in the language they are most comfortable in, they pass on far more than words. They pass on:

• stories;
• humour;
• explanations;
• emotions;
• memories;
• reasoning;
• nuance;
• idioms;
• cultural references;
• ways of telling what has just happened.

Above all, they can take the conversation much further.

That is a fundamental difference. A parent who fully masters a language can explain why someone is being unfair, tell a complex story, talk through a mixed emotion or explore an abstract idea with far more finesse than a parent searching for their words.

How rich the home language is therefore also depends on how richly the parents can actually use it.

The quality of conversations matters as much as the quantity

It is tempting to think in hours: “My child hears two hours of English a day, that’s excellent.”

But two hours of a language are not necessarily two hours of learning of the same quality. Research on bilingual development stresses both the quantity and the quality of exposure to each language, as well as the real opportunities to use it.

A rich conversation carries far more language than a string of simple sentences. Compare:

“Put your coat on. We’re going out.”

with:

“Have you noticed you’re much calmer when we walk down this street? Do you think it’s because there are fewer cars, or just because you know the way better?”

In the second case, the child meets vocabulary, grammatical structures, cause and effect, hypotheses and nuance. Language becomes a tool for thinking — and this kind of exchange is also how critical thinking is built.

Why the family language deserves protecting

In many international families, the family language is gradually replaced by the language of the country, or by English.

That is understandable. English is useful. The local language is essential. Parents want to give their child every possible chance.

But there is a risk: that the child gradually loses the language in which their family can offer the richest conversations. Linguists speak of subtractive bilingualism when a new language does not add to the first one but replaces it. Keeping a family language alive depends largely on the place it keeps in daily life: when it is no longer spoken, it erodes.

So this is not a choice between bilingualism and the family language. It is about building bilingualism without sacrificing the first language.

“But our child mainly needs to learn English”

Yes. And that is precisely the point.

Parents do not need to become their child’s English teachers. If the child attends a school where English is genuinely used every day, they receive substantial, structured exposure to it, in an environment designed for learning. That is the whole difference between bilingual immersion and English lessons.

Home can then keep a different role: the place where the family language is especially rich, natural and full of feeling.

It also avoids asking parents to play a part they may not be equipped for. The role of parents lies elsewhere: talking, telling, explaining, listening.

Parents don’t need a “useful” language: they need a rich one

This may be the simplest principle of all.

• If you are fully at ease in French, speak French with your child.
• If you are fully at ease in Spanish, speak Spanish.
• If you are fully at ease in Arabic, speak Arabic.
• If you are fully at ease in English, speak English.

But if your English is functional while your French lets you explain things ten times more precisely, why give up that richness just because English seems more “useful”?

A language the parent knows in depth is extraordinarily valuable for the child’s language development. And the child can learn other languages elsewhere.

Vocabulary is only part of the question

We often talk about how many words a child knows. But the richness of language goes far beyond that.

Knowing “sad” is not the same as being able to tell apart disappointed, frustrated, hurt, melancholy, worried, discouraged or devastated.

Likewise, being able to say “he’s mean” does not necessarily let a child say: “I think he was unfair to me, but I don’t think he meant to hurt me.”

Precise vocabulary makes it easier to tell situations apart. And that matters especially when a child starts to explain what they think: the finer the distinctions a language offers, the finer the differences they can express between their experiences and ideas.

We should stay careful, though: the relationship between language and thought is complex. A language does not mechanically determine what a child can think. Rather, it gives them resources to categorise, describe, compare and communicate what they experience. (We look at a related question in Do bilingual children really know more words?)

Language helps build more precise thinking

A child says: “I don’t like school.”

That is already information. But an adult with precise vocabulary can help them see more clearly:

• “Are you bored?”
• “Are you afraid of something?”
• “Is the work too easy?”
• “Do you feel you don’t understand?”
• “Is it hard with the other children?”
• “Are you tired?”

Language then breaks an overall experience down into more precise parts. It helps a child move from “I feel something” to “I can tell what I feel, why I feel it, and explain it to someone else”. That is one of the foundations of self-confidence.

A strong family language also passes on a story

There is another, often forgotten dimension. The family language opens up part of the child’s own history: grandparents, family stories, songs, jokes, sayings, memories, cultural references.

When that language disappears, some relationships become harder. A child can love their grandparents deeply without speaking their language; but some nuances become harder to pass on.

Research with multicultural families also highlights how much family habits and parents’ attitudes weigh in keeping a heritage language alive. Keeping the family language is also a way of keeping generations connected.

Should you apply “one parent, one language”?

Not necessarily.

Giving each parent one language can work well in some families. But studies of bilingual families — notably those of the linguist Annick De Houwer — show it is neither the only route nor a guarantee. In real life, practices are much more flexible: a parent mostly speaks one language and sometimes slips into the other, and a rule that is too strict is often hard to keep up over time.

There is no universal recipe. What matters more is that each language gets rich and regular enough exposure. We also discuss this in Can a child learn two languages without mixing them up?

What if the child answers in the dominant language?

This is very common. A parent speaks the family language, the child understands perfectly, but answers in the language they use most with friends or at school.

It does not mean they don’t understand the family language. It may simply mean their language environment is changing.

What matters then is to keep offering chances to speak that language, without turning every conversation into a battle. Stories, meals, games, holidays, calls with family, books, discussions: the language has to stay alive.

Luxembourg: a warning, not a proof

Luxembourg is a particularly interesting case for thinking about multilingualism. Its school system has long been multilingual: Luxembourgish, German and French each play a different role, and French- and English-language tracks also exist.

Yet we should avoid a simplistic conclusion such as: “Luxembourg teaches several languages, so its international test results are weak because of multilingualism.”

The data do not show that. At its last PISA participation, in 2018 (it did not take part in the 2022 round), Luxembourg scored below the OECD average. But those results depend on many factors: social background, migration, languages spoken at home, how schools are organised. More than 80% of the young people tested in Luxembourg mostly spoke a language at home other than the language of instruction; the Luxembourg authorities themselves describe this diversity as a challenge for their schools. The gap in results between advantaged and disadvantaged students was also among the widest.

So Luxembourg does not show that “too many languages make children perform worse”. It raises a far more interesting question:

how can several languages live together in school without competing, at the expense of a deep command of the languages in which a child learns and thinks?

Multilingualism must not mean spreading too thin

This is probably where the real issue lies. We may want to give a child French, English, Spanish, German, Arabic, Chinese…

But every language takes time, exposure, conversation, reading, practice and depth.

So the risk is not necessarily “too many languages”. The risk is exposure that is too thin or too shallow in each of them. Specialists in bilingual development stress how varied bilingual paths are, and how important frequent, high-quality experience in each language is — which is also why the age at which a child starts English matters as much as the way they practise it.

So which language should you speak to your child at home?

There is no universal answer. But one simple rule can be a starting point:

speak to your child in the language in which you can be the richest parent.

The one in which you can:

• tell stories;
• explain;
• joke;
• argue;
• reassure;
• add nuance;
• ask questions;
• talk about feelings;
• discuss abstract ideas;
• tell your family’s story.

Then offer the other languages in settings where they can genuinely be practised and developed. That kind of complementarity is far more fruitful than asking the whole family to speak the same language artificially.

The mother tongue is not the enemy of bilingualism

Quite the opposite. A rich family language can be a solid foundation on which other languages are built.

A child can learn English at school, French in everyday life, Spanish with their grandparents, Italian on holiday. But at home, they can keep the language in which conversations go very deep.

This is not choosing one language against the others. It is giving each language a real and rich enough role.

Languages, yes. Shallowness, no.

Perhaps the real goal is not: “How many languages does my child speak?”

But rather: “In how many languages can my child understand, think, express themselves and communicate precisely?”

Three languages known superficially are not necessarily worth more than two known in depth. And two languages known in depth do not mean the child has to give up the third. It all depends on the quality, frequency and real role of each.

Multilingualism is a wonderful opening. But depth matters as much as number.

At Da Vinci Private School: developing English without erasing French

This is also why bilingualism should not be thought of as replacing one language with another.

At Da Vinci Private School, the week is split equally between French and English, and every child has two teachers: one French-speaking, one English-speaking. Both languages have a real place in learning and in school life.

The aim is not to make French disappear in favour of English. It is to let children gradually build genuine competence in both languages, while keeping a foundation rich enough to learn, reason and communicate precisely. And a child who does not speak English yet can absolutely join us: school brings the English, home can keep its own language.

Discover our bilingual pre-school and our bilingual primary school.

A more fundamental question

For international families, the question can then be asked differently. Before “Which language should we speak to our child?”, perhaps we should ask:

“In which language can we speak to them most richly?”

And then build, around that foundation, an environment that lets them discover other languages.

Because learning several languages is an opportunity. But having one language in which you can get to the heart of things is another.