赵 is listed first in the classical 《百家姓》 (Hundred Family Surnames) because the text was compiled in the Song dynasty, whose imperial surname was 赵. 倩 (a pretty smile) comes from 《诗经》: 巧笑倩兮 — 'her pretty smile so charming'.
mistakes
The name reading is Qiàn (fourth tone). The character 倩 also has a second reading qìng used in some personal names, but modern standard is qiàn.
