Researchers have known for some time that maternal breast milk provides critical nutrients for newborns, and antibodies from mothers vaccinated against a specific disease-causing bacterium or virus can be transferred via breast milk to babies. Now a new preclinical study by Weill Cornell Medicine investigators shows that one specific set of antibodies that is induced naturally by gut beneficial bacteria can be transferred from mothers to infants through breast milk and help infants defend against infection-induced diarrheal illness. The study suggests boosting these “naturally-produced” antibodies in mothers might enhance infants’ immunity against bacterial pathogens that cause infectious gastrointestinal diseases.