Princess Kako, a grandchild of Emperor Akihito and the younger daughter of Prince Akishino and Princess Kiko, turned 24 on Saturday.

The princess, who performs official duties while studying at International Christian University in Tokyo, has drawn attention to the kind of activities she will engage in after she graduates next year.

She has been busy writing her graduation thesis, her father said last month. In June, she returned from Britain after spending nine months at the University of Leeds as an exchange student.

The princess studied performing arts as well as psychology, her major at ICU, at the British university and spent her spring vacation in Portugal and Spain.

The princess vowed on the occasion of her 20th birthday to do her best in every official duty she performs as an adult member of the Imperial family. Since returning home, she has attended youth events and greeted people in sign language at a contest for high school students in Tottori Prefecture in October.

Princess Kako's father and her younger brother Prince Hisahito, 12, will be first and second in line to the throne, respectively, after the Emperor, 85, abdicates on April 30 next year. Her uncle Crown Prince Naruhito will ascend the throne the following day.

Her sister Princess Mako, 27, has postponed her marriage to Kei Komuro, her boyfriend from her time at ICU, following reports about a financial dispute involving his family.