Though "Kugyobunin" (directory of court nobles) and "Honcho Koin Jounroku" (the Emperor's family tree, made in Muromachi period) says that she was a princess of Emperor Uda, the age difference between Junshi and Emperor Uda was only nine years, so it is possible that they were a brother and sister, but unlikely that they were a father and a daughter.
『公卿補任』や『本朝皇胤紹運録』は、宇多天皇の皇女としているが、順子と宇多天皇の年齢差が僅か9歳であることから、兄弟関係であったとしても、父子関係であったとは考え難い。