Japan's Prince Hisahito, the only son of Prince Akishino and Princess Kiko, poses with his sisters, Princess Kako (L) and Princess Mako (R) at a rice fieldof the Akasaka Detached Palace in Tokyo, Japan in this handout picture taken August 10, 2016, and provided by the Imperial Household Agency of Japan. Prince Hisahito turned 10 years old on September 6, 2016. Imperial Household Agency of Japan/Handout via Reuters