Prince Hisahito, who turns 13 years old on Sept. 6, enters Ochanomizu University Junior High School in April, pays a courtesy visit to Bhutan's king and queen in August, and is accompanied by his parents on their official duties with the aim of nurturing a wide vision for him. (The Asahi Shimbun)

Prince Hisahito, who is now second in line to the Chrysanthemum Throne after his uncle Emperor Naruhito's enthronement in May, celebrated his 13th birthday on Sept. 6 after his first overseas trip.

Hisahito, the son of Crown Prince Fumihito and Crown Princess Kiko, and the youngest grandchild of Emperor Emeritus Akihito and Empress Emerita Michiko, visited Bhutan during his summer vacation in August.

Hisahito showed curiosity about dragonflies and cicadas in the Himalayan kingdom's mountains as he is knowledgeable about insects, according to sources.

Hisahito communicated with Bhutan's royal family members, and had experiences to understand Japan better through observing the country’s culture and plants that are similar to those of his own country and comparing them, according to the Imperial Household Agency.

As for his school life at Ochanomizu University Junior High School in Tokyo, which he entered in April, Hisahito energetically plays outside with his friends during breaks between classes.

While attending the school's sports festival in June he participated in a 50-meter obstacle race and “centipede race,” involving teams whose members’ ankles are tied together.

He also joined the cheering squad composed of children of various school grades.

In addition, Hisahito performed in a play in English during an overnight activity.

Meanwhile, as an imperial family member, Hisahito accompanied Fumihito and Kiko during their official duties.

Hisahito communicated with children from Okinawa Prefecture and Hokkaido, who were engaged in covering news of Tokyo for a school newspaper, at the Akasaka Estate residence in Tokyo's Minato Ward in July. He listened attentively to their presentations on local nature and culture studies.

Hisahito has also devoted himself to cultivating rice and vegetables such as mizuna lettuce, spinach or cabbage throughout the past year.