Is Bilingualism Slowing Speech Development or Causing Speech Delay?

Singapore is a multilingual society in fact. Young children may hear English in school. They may hear Mandarin at home. They may hear another language or dialect from their grandparents and other family members. Parents may naturally wonder about the implications of multilingualism for their children within reason.

“Is bilingualism confusing my child?”

“Is the mixing of languages slowing down speech?”

“Would my child speak faster if we used only one language?”

These questions are likely to arise even more if your child is a late talker, has trouble expressing themselves, or appears to understand one language better than the other. But there is good news for sure! Decades of varied research show bilingualism does not cause speech delay.

Children who speak two languages may develop speech and language skills at a slower rate than peers who speak only one language, or communication patterns may differ according to expectations. This explanation can ease worries and aid parents as they choose when to get expert care.

Bilingual children reach the same milestones as monolinguals regarding babbling, saying their first word around age 1, and starting to create two-word phrases between 18 and 24 months. The path is the same, but vocabulary and language skills are distributed differently.

Bilingualism Does Not Cause Speech Delay — Here’s Why

Parents often worry that two languages might “overload” a young child’s brain. In reality, the developing brain is exceptionally equipped to handle more than one language — it’s built for it. Children learning two languages follow the same developmental path as monolingual children: they babble, say first words, and start combining words around the same ages. What changes is not when they hit milestones, but how the vocabulary is spread across their two languages.

A bilingual toddler might have 15 English words and 20 Mandarin words while a monolingual toddler has 35 in one language. To an adult, the bilingual child looks like they have fewer words in each language, but in terms of total vocabulary, they are exactly where they need to be. Many parents also don’t realise that bilingual children often understand far more than they can express, especially in the less dominant language. So while it may feel like bilingualism is slowing things down, the child is actually building two language systems at once — a process that can look uneven from the outside, but is completely normal.

Why Bilingual Children Sometimes Appear Delayed

Although bilingualism is not the cause of delays, bilingual families may encounter situations that look like slower development. These are misunderstandings rather than genuine developmental problems.

1. Their vocabulary is split across two languages

A parent evaluating progress based on English alone might conclude their child is “behind,” when the child actually has a strong total vocabulary — just distributed across both languages. Because parents rarely combine counts across languages, the vocabulary looks smaller than it is.

2. One language is stronger than the other

Children tend to favour whichever language gives them the most mileage. If English dominates at school, Mandarin or Malay may lag slightly behind. That imbalance often gets mistaken for delay when it’s really just uneven input.

3. Code-switching gets misunderstood

Mixing languages (“Mama, I want 饼干”) is not a red flag — it’s a sign that the child is drawing from all the language resources available to them. Adults do this too in everyday Singaporean speech. Children aren’t confused; they’re efficient.

4. A real delay, unrelated to bilingualism, happens to co-exist

Some children are late talkers regardless of language exposure. Others may have underlying issues with social communication, hearing, articulation, or overall language processing. When a bilingual child has a true delay, it becomes visible in all languages — not because of bilingualism, but despite it.

When Should Parents Be Concerned About a True Delay?

The easiest way to think about it is this:

A bilingual child should still show progress in any language they are exposed to consistently.

Look out for:

• No words by 18 months
• Very limited vocabulary (across both languages combined) by age 2
• No two-word combinations by 2½
• Difficulty understanding simple instructions in any language
• Struggles to express themselves even in their strongest language
• Speech that is unclear beyond what’s typical for age
• Limited imitation or difficulty taking turns during communication

If these issues appear across all languages, it’s worth speaking to a speech-language therapist for a proper evaluation.

Should Parents Reduce to One Language to Speed Things Up?

This is one of the most common instincts parents have, and ironically, it often backfires. A child learns language best in the one they hear the most naturally and consistently. If a parent switches to English when they’re more comfortable in Mandarin, the language model becomes less rich and less emotionally connected. Children pick up on that.

Reducing to one language rarely accelerates progress. What actually helps is quality, intentional interaction — regardless of which language it’s in.

The Real Advantages of Growing Up Bilingual

Research consistently shows long-term benefits for bilingual children. They often develop stronger skills in cognitive flexibility, problem-solving, and perspective-taking. Socially and culturally, children stay connected to family and heritage. Academically, they gain access to more vocabulary and broader literacy skills over time.

Bilingualism is not a burden. It’s a strength — one that pays off well into adulthood.

Practical Ways Parents Can Support Bilingual Speech Development

Keep languages meaningful, not mechanical.

Use them during daily routines, play, and conversations — not forced drills.

Respond in the language you’re most natural in.

Children learn best from confident models.

Read in both languages.

Books expose children to vocabulary they won’t hear in daily conversation.

Don’t worry about mixing.

Children will naturally sort languages out as their systems mature.

Pay attention to progress, not perfection.

Even small, consistent gains matter more than which language they appear in.

Seek early support if you’re uncertain.

A therapist can quickly tell the difference between bilingual patterns and genuine delays.

Final Thoughts

Raising a bilingual child can sometimes feel like navigating a maze of mixed advice, especially when speech seems to be developing a little differently from what you expected. But bilingualism itself isn’t the culprit — it’s a natural, healthy part of growing up in a multilingual environment like Singapore. What matters most isn’t choosing the “right” language, but giving your child rich, responsive interactions in the language you’re most comfortable using.

If your child is showing progress — even if it’s uneven across languages — that’s a good sign their communication system is growing. And if certain signs or behaviours still leave you wondering, it’s perfectly okay to seek clarity. A speech-language therapist can help you understand whether what you’re seeing is part of normal bilingual development or a genuine speech delay that needs early intervention.

At the end of the day, language learning is not a race. Every child develops at their own pace, with their own strengths, quirks, and ways of connecting with the people around them. With patience, consistency, and the right guidance, your child can thrive in both languages — and enjoy the lifelong advantages that come with being bilingual.

If you ever need help making sense of your child’s communication milestones, don’t hesitate to reach out for a professional child speech therapist for assessment. Early understanding brings peace of mind, and early support can make all the difference.