Prince Hisahito turns 20 as Japan's government reinforces male-only succession rules

• Hisahito, the nephew of Emperor Naruhito, is second in line to Japan's 1,500-year-old Chrysanthemum Throne and the youngest of 16 members of the rapidly shrinking and aging imperial family.
• The child who loved animals and bugs, especially dragonflies, is now a sophomore majoring in biology at