For more than three decades, researchers have known that children from larger families are less likely to develop allergic disease, but the potential reason for that has remained a mystery.
Researchers from Barwon Health, Deakin University and Murdoch Children's Research Institute have used long-term data from the Barwon Infant Study to demonstrate how older siblings speed up the rate at which babies develop their gut microbiome, which protects them from allergic disease.
Article from ABC News