Severn Suzuki, in a speech to the UN from 1992.

The Girl Who Silenced the World at the UN

Born and raised in Vancouver, Severn Suzuki has been working on environmental and social justice issues since kindergarten. At age 9, she and some friends started the Environmental Children’s Organization (ECO), a small group of children committed to learning and teaching other kids about environmental issues. They traveled to 1992’s UN Earth Summit, where 12 year-old Severn gave this powerful speech that deeply affected (and silenced) some of the most prominent world leaders. The speech had such an impact that she has become a frequent invitee to many UN conferences.

Original Source: http://www.karmatube.org