Parent question
Does learning two languages cause speech delays?
Published · Updated
The short answer
No. ASHA says using more than one language doesn’t confuse children or cause speech or language delays, and that a genuine difficulty shows up in all the languages a child uses. Bilingual children can look behind if you count only one of their languages, so an assessment should consider all of them. Keep using the language or languages you’re most comfortable with at home.
What’s normal
- Mixing words or grammar from different languages is an expected part of learning more than one language (ASHA).
- Many fluent multilingual speakers switch between languages. In children learning two languages from birth, this follows grammatical patterns rather than happening randomly (ASHA Practice Portal).
- A sound pattern from one language carrying into another (transfer) isn’t in itself a speech sound disorder (ASHA Practice Portal).
What research says
- A systematic review of 66 studies found limited evidence that bilingual children develop speech more slowly than monolingual children, though there were differences in error patterns, more variation, and transfer between languages. It also noted that bilingual children with speech difficulties may be under-referred (Hambly et al., 2013).
- In 47 Spanish–English bilingual toddlers aged 22 to 30 months, total vocabulary across both languages was similar to monolingual toddlers’, while vocabulary in a single language was smaller (Core et al., 2013).
- Skill in each language tracked how much the child heard that language (Hoff et al., 2012).
These vocabulary studies were of Spanish–English toddlers in the US, but they show why counting only one language can make a bilingual child look behind.
When to ask a speech therapist
- Your child has the same difficulty in every language they use.
- People who speak your child’s languages often find them hard to understand for their age.
- You’re worried. Bilingual children with speech difficulties may be under-referred, so it’s worth asking.
Ask for an assessment that considers all of your child’s languages and dialects. ASHA advises clinicians to allow responses in all of them. In the US you can ask for a free evaluation in your state.
Questions parents ask
Should we stop speaking our home language?
No. ASHA advises talking to your child in the language or languages you’re most comfortable using, and encourages SLPs to support families’ multilingualism.
Is it normal for my child to mix languages?
Yes. Mixing words or grammar from different languages is an expected part of learning more than one language.
Can a bilingual child have a speech sound disorder?
Yes, like any child. A real difficulty shows up across all their languages, and an assessment should consider each of them.
Sources
- ASHA / Communication Health Support Association: Learning more than one language.
- ASHA Practice Portal: Multilingual service delivery in audiology and speech-language pathology.
- ASHA Practice Portal: Speech sound disorders (articulation and phonology).
- Hambly, H., Wren, Y., McLeod, S., & Roulstone, S. (2013). The influence of bilingualism on speech production: A systematic review. International Journal of Language & Communication Disorders, 48(1), 1–24.
- Core, C., Hoff, E., Rumiche, R., & Señor, M. (2013). Total and conceptual vocabulary in Spanish–English bilinguals from 22 to 30 months: Implications for assessment. Journal of Speech, Language, and Hearing Research, 56(5), 1637–1649.
- Hoff, E., Core, C., Place, S., Rumiche, R., Señor, M., & Parra, M. (2012). Dual language exposure and early bilingual development. Journal of Child Language, 39(1), 1–27.