1. A combination of S sisters is called ASOS. The elder sister is Xu Xiyuan, so it is Big S, and the younger sister is Xu Xidi, so it is called Little S. They are biological sisters, the elder S Xu Xiyuan is the second child and the younger S Xu Xidi is the third child.

2. Road to fame: Barbie Hsu (Big S), born on October 6, 1976 in Taipei, Taiwan, is an actress, singer, host and writer in Taiwan, China. Originally an artist under Venus Entertainment Brokerage Company. In the early days, she focused on hosting programs and singing. She made her debut at the age of 17 with the song "Ten Minutes of Love", and later formed the "ASOS" singing group with her sister Xu Xidi (little S). The two also hosted the "Entertainment 100" program of the eight major TV stations GTV "Percent" variety show. In 2001, she participated in "Meteor Garden" and became popular as "Shan Cai". She was nominated for the Golden Bell Award for Best Actress for this TV series. In 2002, big S Xu Xiyuan made her first appearance in Guangzhou and attended the advertising premiere ceremony held at China Plaza. In 2004, Big S wore a gorgeous outfit to attend a press conference celebrating the beauty book "Beauty King". Because the book was reprinted seven times in just two weeks and sold 100,000 copies, making Big S Xu Xiyuan a million-seller. The ranks of writers. In 2007, Miss Xu Xiyuan appeared at the 44th Golden Horse Awards in Taipei and walked the red carpet in a one-shoulder orange dress. In 2010, they officially left their agent Wang Weizhong, and the sisters established their own business with two companies, "Taiping" and "Douxiang". On November 16 of the same year, they got engaged to Wang Xiaofei in Beijing. On March 22, 2011, Xu Xiyuan and Wang Xiaofei held their wedding in Hainan. In 2012, she appeared at the beauty industry event "OL Direct Selection·Perfect Brand Awards" award ceremony. Xu Xiyuan won the Greater China "OL Favorite Brand Spokesperson" award for Pantene Clinicare.

Xu Xidi (little S) was born on June 14, 1978 in Taipei City, Taiwan Province. Her ancestral home is Tancheng, Shandong Province. She is a host, singer and actor in Taiwan, China. In 1994, he formed the singing group SOS (later renamed ASOS) with his sister Big S and debuted, and also participated in drama performances. From 1998 to 2006, he hosted "Entertainment 100%" and was loved by young audiences. In 2000, he collaborated with his sister again and released the album "Abnormal Girl". Since 2004, he has hosted the variety show "Kangxi Is Coming" with Cai Kangyong. With this show, he won the Best Variety Show Host Award at the 40th Golden Bell Awards in 2005, and became popular in the Chinese-speaking area and received widespread attention. Married Xu Yajun in 2005 and have three daughters. In 2013, he ranked 27th on the Forbes China Celebrity List. From 2007 to 2008, he and his sister Big S hosted the food program "Big and Little Love to Eat" which also received good ratings. Xiao S has served as the host of Taiwan's Golden Horse Awards, Golden Melody Awards and Golden Bell Awards galas for many times.