Supernanny, real name Jo Frost, has reacted to Prince William and Princess Kate’s son Prince Louis’ behaviour at Trooping the Colour. The five-year-old royal danced, yawned, and pulled faces during King Charles’ birthday parade. Supernanny, real name Jo Frost, has reacted to Prince William and Princess Kate’s son Prince Louis’ behaviour at Trooping the Colour. The five-year-old royal danced, yawned, and pulled faces during King Charles’ birthday parade.