Six-year-old Antoni, born in the UK to Polish parents, speaks only a few English words in class and often looks confused when the teacher gives instructions. He could simply be adjusting to English - or the problem could be developmental language disorder (DLD), a condition that severely impairs a child's ability to learn, use and understand spoken language.
Authors
- Teresa Garrido-Tamayo
Visiting Researcher in Speech and Language Sciences, Newcastle University
- Carolyn Letts
Senior Lecturer in the School of Education, Communication and Language Sciences, Newcastle University
- Laurence White
Reader in Speech Science, Newcastle University
Such challenges are increasingly common for parents and teachers. In England, for example, around 21% of schoolchildren are growing up with a first language other than English . While most children's language development - whether monolingual or multilingual - is typical, the average classroom includes two DLD-affected children. DLD's prevalence, roughly 8% , is similar worldwide, from China to Mexico .
Even so, DLD remains under-recognised and under-served - especially compared to other developmental conditions , such as dyslexia, autism or attention deficit hyperactivity disorder (ADHD).
Identifying DLD in multilingual children can be difficult. Each language a child learns develops at its own pace, depending on factors such as how often they hear and use it . For example, multilingual children may temporarily lag behind their monolingual peers in vocabulary in one language, but this should not be mistaken for DLD.
Children with DLD show problems across all their languages and need specialist help. In contrast, those with typically developing language only struggle in the language they need more exposure to, like English at school.
Learning two or more languages promotes linguistic , social and cognitive strengths in all children. Contrary to longstanding myths that multilingualism harms language development, learning multiple languages does not cause or exacerbate DLD. Support for DLD should sustain all of a child's languages, as these are critical for wellbeing, identity and family relationships .
The impact of DLD is lifelong and extends far beyond language . It has consequences for mental health , socialisation , literacy, academic performance , and quality of life . Accurate, timely diagnosis and support are essential, not just for individual life chances, but also for society. Adults with DLD are more likely to have difficulty getting a job and have a criminal record .
Addressing DLD
These are key signs that a multilingual child may be at risk for DLD, suggesting an approach to a speech and language therapist . These if they:
are slower to say first words, or put words together, than siblings
struggle to understand what others say or follow instructions
have trouble expressing thoughts or telling stories
rely excessively on gestures (like pointing) to communicate instead of words
are slower to learn English in school than peers with similar age, cultural and linguistic backgrounds
struggle to interact with children who speak the same languages.
Following referral, speech and language therapists gather information from parents, teachers, tests and other sources, aiming to understand the child's abilities in all their languages .
In linguistically diverse countries, there are still considerable obstacles , however. UK-based speech and language therapists , for example, still lack reliable tools to equally assess English and the children's additional languages. With few speech and language therapists having multilingual proficiency, and a shortage of appropriately trained interpreters, DLD can be missed - or typical multilingual development mislabelled as disordered - thus delaying or misdirecting support.
Progress is being made, with promising new tools like the UK bilingual toddlers assessment tool and the language impairment testing in multilingual settings battery . The former uses two-year-olds' vocabulary in British English and their other language, alongside their exposure to each language, to determine whether their language development may be at risk.
Similarly, the Litmus battery includes tools for assessing the language skills of multilingual children from a range of ages and language backgrounds, such as phonological memory and storytelling.
More recently, our team is developing a dynamic assessment resource at Newcastle University that uses enjoyable activities to detect DLD. It explores multilingual children's learning potential - not just their existing skills - in language and communication areas affected by the condition, such as telling stories or recognising emotions in people's voices.
Detecting DLD is the first step. Support from family, schools and speech and language therapists can then transform a multilingual child's life outcomes, helping them grow up healthier and happier.
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Teresa Garrido-Tamayo received PhD funding from the Economic and Social Research Council via the Northern Ireland and North East Doctoral Training Partnership from 1st October 2019 to 31st May 2023.
Laurence White received funding from the Economic and Social Research Council from 1st August 2013 to 31st July 2016 (ES/K010123/1 - "Lexical Development in Bilingual Toddlers" - Principal Investigator, Caroline Floccia, University of Plymouth).
Carolyn Letts does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.