Catherine, the Duchess of Cambridge, and her husband, Britain’s Prince William, watch as their son Prince George reacts after unveiling a plaque to commemorate their visit to the enclosure for the Australian animal called a Bilby at Sydney’s Taronga Zoo

Catherine, the Duchess of Cambridge, and her husband, Britain’s Prince William, watch as their son Prince George reacts after they unveiled a plaque to commemorate their visit to the enclosure for the Australian animal called a Bilby during a visit to Sydney’s Taronga Zoo April 20, 2014. The Prince and his wife Kate are undertaking a 19-day official visit to New Zealand and Australia with their son George. REUTERS/David Gray (AUSTRALIA – Tags: ROYALS ENTERTAINMENT)