THE new crown princess's two younger sisters, Reiko and Setsuko, were in Hongkong two months ago. But it was a closely kept secret. They were here for a brief visit and no one wanted this turned into a media event with photographers dogging their footsteps wherever they went. Reiko and Setsuko are twins, born on July 8, 1966. As it transpired, no one knew who the two girls were as they shopped at the Ladies' Market in Mongkok, visited historical sites and took in what is left of Hongkong's old architecture. The twins spent four days here as guests of the Japanese Consul-General, Masaki Orita, an old friend of the family and a diplomatic colleague of their father. Reiko, who is with the United Nations High Commissioner for Refugees (UNHCR) and currently based in Hanoi, also visited Hongkong for a week in January, staying with the Oritas. That visit was also kept a closely guarded secret as the announcement of the engagement of her elder sister Masako to Crown Prince Naruhito had only just been made. In April, Reiko decided to come along with her twin sister, Setsuko, who had graduated from the Faculty of Literature at the Tokyo University. After a short stint at the Honda Motor Co, she is back at university studying cultural anthropology. Mr Orita, who has known the family since the early 1970s, remembers the three girls as children. ''All of them went to the same school. When I used to visit their home, I used to see their three caps and school coats hanging from the wall,'' recalled Mr Orita, who, until his posting to Hongkong last year, was executive assistant to former prime minister Toshiki Kaifu. Naturally, Mr Orita was protective of the two girls, especially since the announcement of their sister's engagement to the crown prince. As executive assistant in charge of Foreign Affairs in the prime minister's office, Mr Orita also came to know their elder sister, Masako, professionally. ''Ms Owada had, several times, acted as interpreter when important visitors came to visit Prime Minister Kaifu,'' Mr Orita said. Mr Orita came to know Hisashi Owada, the diplomat father of the three girls, when he was a member of the treaties division of the Japanese Foreign Ministry. At that time, Mr Owada was the director of that division. It was 1974. When Mr Owada became director general of the treaties division 10 years later, Mr Orita was the head of the division. Three years later, their professional paths crossed again when Mr Owada was the deputy minister of administration and Mr Orita was head of the overseas division of the foreign ministry.