Princess Kako, the niece of Japanese Emperor Naruhito, turned 28 on Thursday, having spent the past year actively taking on the official duties of her older sister Mako Komuro, who left the imperial family after marrying her commoner boyfriend.

The younger daughter of Crown Prince Fumihito and Crown Princess Kiko has expressed hopes that society will evolve into one where people are offered a wider range of choices in life to realize their full potential, according to the Imperial Household Agency.

"This hope appears to be strengthening as (the princess) experiences various things in life," her attendants said.

Princess Kako is pictured at the Akasaka Estate in Tokyo on Dec. 2, 2022. (Photo courtesy of the Imperial Household Agency)(Kyodo)

Resuming visits to regional areas that were suspended due to the COVID-19 pandemic, the princess attended an urban greenery fair held in Hokkaido in July and a sign-language contest for high school students in Tottori Prefecture, western Japan, in September.

She also attended Girl Scouts events in Nagano Prefecture and Tokyo in August and October, respectively, where she was encouraged by efforts being made by younger generations to realize gender equality and tackle environmental issues, according to the agency.

Princess Kako has been actively engaging in duties left by her sister Mako as she took over as honorary president of the Japan Tennis Association and president of the Japan Kogei Association. She also attended urban green infrastructure events that her sister used to attend.

The former princess, 31, moved to the United States after marrying her commoner boyfriend Kei Komuro in October last year.

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