Princess Aiko, the only child of Crown Prince Naruhito and Crown Princess Masako, turned 14 years old Tuesday.

As this year marks the 70th anniversary of the end of World War II, the princess, who is now in her second year at Gakushuin Girls' Junior High School in Tokyo, has been studying the war through an exhibition, books and the media, the Imperial Household Agency said.

During summer vacation, Princess Aiko accompanied her parents to an exhibition in Tokyo on memories of the war. She also observed a moment of silence on Aug. 15 with her family to mark the 70th anniversary of Japan's surrender.

As a homework assignment, the princess wrote about her feelings on reading newspaper articles commemorating the war's end and discussed it with her grandmother, Empress Michiko, at the Imperial residence.

During a sports event at her school in April, the princess chose to take part in softball, which her mother also played when she was in junior high school.

She also enjoys playing tennis with her parents.

Princess Aiko, who has rarely been absent from school, completed a swim of around 3 km during a school excursion to Numazu, Shizuoka Prefecture, during the summer.

The princess cannot ascend the throne because only males may do so under the Imperial Household Law.