Princess Aiko, the only child of Emperor Naruhito and Empress Masako, is pictured on Nov. 24, 2023, at the Imperial Palace in Tokyo. (Photo courtesy of Imperial Household Agency)(Kyodo)

Princess Aiko, the only child of Emperor Naruhito and Empress Masako, on Friday turned 22 amid her final year of university in which she is balancing her studies with a wide range of official duties as a member of the Japanese imperial family.

Her official duties have allowed the princess to connect with the history and traditions of the imperial family, reaffirming her understanding of its responsibilities, according to the Imperial Household Agency.

Currently a fourth-year student at Gakushuin University's Faculty of Letters, the princess has been studying on campus in person since last spring after attending classes online during the coronavirus pandemic.

She has been taking various courses, including welfare and physical education, and deepening her knowledge of the literature and poetry of the Heian, Kamakura, Edo and Meiji eras. She has recently been spending her free hours working on her thesis, the agency said.

Princess Aiko, who enrolled in the university in 2020, is not eligible to ascend the Chrysanthemum Throne, as the 1947 Imperial House Law does not permit females to do so.

The princess in October joined her parents on a visit to the Japanese Red Cross Society headquarters for an exhibition marking the centenary of the Great Kanto Earthquake. She laid flowers at a cenotaph dedicated to doctors and nurses who died in wars or disasters while serving, her first time officially offering a floral tribute.

She said she was nervous for her first appearance at a public New Year greeting event at the Imperial Palace early in 2023, but gradually became acclimated to the atmosphere and was relieved when the event went smoothly, according to the agency.

At the palace, the princess has been taking care of her dog "Yuri" and cats "Mii" and "Seven," and has also grown vegetables, including Chinese cabbages, cucumbers and eggplants, which she ate with her family.

In addition to taking walks with her parents, she plays tennis, volleyball and badminton with agency officials, the agency said.