Question: When was the American-born former Japanese pop singer born who was debuted in February 2003 and also a belongs to the category of  "Dekichatta kekkon"?

Context articles: Riho Sayashi
Azumi Uehara
Akari Uemura
Dekichatta kekkon
Mai Hagiwara
Saki Ogawa
Melody (Japanese singer)
Shiori Takei
Rio Fujii
Momoko Tsugunaga

Riho Sayashi (鞘師里保 "Sayashi Riho", born May 28, 1998, Hiroshima, Japan) is a Japanese pop singer under Hello!
 Project.
 She is a former ninth generation member of the Japanese pop group Morning Musume, along with Mizuki Fukumura, Erina Ikuta, and Kanon Suzuki.
 Her uncle, Tomoya Sayashi, is a former Japanese baseball player of the Hiroshima Toyo Carp of Japan's Central League.
 She is also a former member of the duo Peaberry.
Azumi Uehara (Japanese: 上原 あずみ , Hepburn: Uehara Azumi , born April 10, 1984) is a Japanese adult video (AV) actress and former Japanese pop singer
Akari Uemura (植村 あかり , Uemura Akari ) is a Japanese pop singer and idol pop singer signed to Hello!
 Project as a member of Japanese pop idol group Juice=Juice and Hello!
 Pro Kenshuusei.
 She was first introduced at the 2012 March "Nama Tamago Show!"
 concert.
 Her official nickname is Ārī (あーりー ) .
In Japan, the slang term "Dekichatta kekkon" (出来ちゃった結婚 ) , or "Dekikon" (デキコン ) for short, emerged in the late 1990s.
 The term can literally be translated as "oops-we-did-it-marriage," implying an unintended pregnancy.
 Notable celebrities with these marriages include Namie Amuro, Yōko Oginome, Hitomi Furuya, Ami Suzuki, Kaori Iida, Nozomi Tsuji, Anna Tsuchiya, Meisa Kuroki, Leah Dizon, Melody Miyuki Ishikawa, and Riisa Naka.
 A quarter of all Japanese brides are pregnant at the time of their wedding, according to the Health Labor and Welfare Ministry, and pregnancy is one of the most common motivations for marriage.
 Unplanned pregnancies are common due to low usage of oral contraceptives by women.
 The prevalence and celebrity profile of "dekichatta-kon" has inspired Japan's wedding industry to introduce an even more benign phrase, "sazukari-kon" (授かり婚 , blessed wedding) .
Mai Hagiwara (萩原 舞 , Hagiwara Mai , born February 7, 1996 in Saitama Prefecture) is a former Japanese pop singer and actress.
 At age 6, she auditioned for Hello!
 Project Kids in 2002 and later became part of the girl group Cute under the Hello!
 Project collective.
Saki Ogawa (小川 紗季 , Ogawa Saki ) is a former Japanese pop singer, best known as one of the 4 founding members of the Japanese pop group S/mileage.
Melody (born February 24, 1982) (stylized melody.)
 is an American-born former Japanese pop singer and television host.
 She debuted in February 2003 with the song "Dreamin' Away", under Toy's Factory.
 In October 2008, Melody announced on her blog ending her career as a music artist to focus on pursuing a career as a fashion designer.
Shiori Takei (竹井 詩織里 , Takei Shiori ) is a former Japanese pop singer and songwriter who recorded under the Giza studio label.
Rio Fujii (藤井 梨央) (born March 4, 1999) is a former Japanese pop singer, and former member and sub-leader of Japanese girl group Kobushi Factory.
Momoko Tsugunaga (嗣永 桃子 , Tsugunaga Momoko , born 6 March 1992) is a former Japanese pop singer, actress, and radio personality.
 Tsugunaga joined Hello!
 Project as a member of Hello!
 Project Kids at the age of 10 and later became part of the girl groups Berryz Kobo and Buono!
 Following Berryz Kobo's hiatus, she became the playing manager of Country Girls.
 In 2017, she retired from the entertainment industry to work in the education field.