“Clinically we occasionally see 2-year-old children with an inquiry of speech delay and they want to verify normal hearing prior to an SLP referral. And sometimes the child is learning two languages at the same time at home. If there is a speech delay (or concern about a speech delay), should the parents be encouraged to only speak English at home, or continue with the two languages?”
Families should be encouraged to continue speaking the two (or more!) languages that they naturally use at home. The reason for this answer is multifaceted.
First, current research highlights that children are remarkably capable of learning multiple languages. When they are developing their language learning systems, very young children can cognitively process different languages and learn the linguistic rules underlying each language. Learning multiple languages is not a cause for speech or language disorders.
For children who do have a speech or language disorder, there is no evidence that learning multiple languages will hinder the child’s development. When speech-language pathologists assess children learning multiple languages who they suspect have a language learning disorder, they consider all languages that the child is learning. If a child is having difficulty learning language, then they will struggle learning any language in their environment regardless of the number.
Advising families to refrain from speaking their home languages with their child will not help the child overcome any underlying speech or language disorder. In fact, advising families to withhold their home languages can cost children valuable language learning opportunities as well as important connections to their home culture. These opportunities and connections are necessary to support children’s language learning. Many interventions used by speech-language pathologists focus on increasing the amount and type of language that children hear, not decreasing!