Princess Aiko, the daughter of Crown Prince Naruhito and Crown Princess Masako, turned 10 on Dec. 1.
The Imperial Household Agency said Aiko attended almost all her classes at Gakushuin Primary School in the past two months, and that her mother is accompanying her to school and during lessons less often than before.
Previously, the fourth-grader skipped many classes after she developed anxiety about attending school in February last year.
In June, Aiko joined the school orchestra, playing the cello.
She participates in the orchestra’s practice sessions in the morning and after school, and plays dodge ball and soccer with her classmates during breaks and after school, according to the agency.
Developing symptoms of what was believed to be mycoplasma pneumonia, Aiko was hospitalized at the University of Tokyo hospital between Nov. 1 and Nov. 5.
She was grateful to her doctors, and she said that the experience has taught her many things, according to the agency.
When Emperor Akihito was admitted to the same hospital for bronchial pneumonia from Nov. 6 to Nov. 24, Aiko sent him tangerines and flowers grown in the garden of her residence via Naruhito, who visited his father at the hospital.
Aiko offered a silent prayer for the victims of the Great East Japan Earthquake and tsunami on April 11, a month after the disaster struck.