"What if I was to tell you that a game of peek-a-boo could change the world?" asks seven-year-old Molly Wright, one of the youngest-ever TED speakers. Breaking down the research-backed ways parents and caregivers can support children's healthy brain development, Wright highlights the benefits of play on lifelong learning, behavior and well-being, sharing effective strategies to help all kids thrive by the age of five. She's joined onstage by one-year-old Ari and his dad, Amarjot, who help illustrate her big ideas about brain science. (This TED Talk was produced in collaboration with Minderoo Foundation as an educational tool for parents and caregivers around the world and is supported by UNICEF.)