The American Academy of Pediatrics hosts its annual National Conference & Exhibition in San Diego for the first time in over a decade, offering the latest information in medical research, education and advocacy for children’s health Oct. 2 – 6, 2026. 

Overhearable speech (speech that may occur when caregivers are talking to each other in the child’s presence), constitutes over half of children’s language exposure, but its role in language development remains underexplored. Researchers from the University of Chicago, The New School for Social Research and Princeton University examined when and how English-learning children growing up in the United States understand words that they overheard from their parents’ conversations at home. The present study focused on word learning and researchers compared children’s recognition of words that parents reported as primarily overhearable to children (i.e., “high-overheardness” words associated with adult talk such as pot, salad, and charger) with words that parents reported as primarily directed to children (i.e., “low-overheardness” words such as zipper, mirror and oatmeal). 

The findings show that 24- and 30-month-olds could recognize high-overheardness words and 18-month-olds were not able to recognize these words. However, 18-month-olds with larger vocabularies by 24 months showed better recognition of high-overheardness words and a smaller recognition gap between high- and low-overheardness words than peers with smaller vocabularies. This suggests that early world learning is dynamic and changes alongside children’s developing language abilities and social experiences. 

The research is featured in a new Child Development article “Developmental change in acquiring overhearable words from naturalistic contexts” by Yuchen Jin (University of Chicago), Ruthe Foushee (The New School for Social Research), Kennedy Casey (Princeton University) and Marisa Casillas (University of Chicago).