Relations between home language exposure and vocabulary development in bilingual toddlers

This study examined the relation between home language exposure from different household members, specifically older siblings and English and Spanish vocabulary development in bilingual toddlers. The English and Spanish vocabularies of 38 toddlers (19 boys and 19 girls; M age = 2.14 years, SD = .14) were measured. Parental English use was found to be the strongest predictor of English and Spanish proficiencies. Among households in which the parents use less than 10% English, having older siblings had no effect on English language proficiency but was associated with lower levels of Spanish proficiency.