There was a custom developed over generations that both the eastern and western family heads of the Otani Family's having lineage from Shinran, who was a son of the court noble Arinori HINO, and Hirotsuna HINO (Kakunyo's father) were adopted by influential court nobles; consequently, both the Otani families have increasingly been related to court nobles considering the maternal line, since they kept marriages with court nobles over generations.
もともと公家の日野有範の子息である親鸞と、日野広綱（覚如の父）の血統を引く東西両大谷家当主は、代々有力公家の猶子になる慣習があり、また、代々公家と通婚を続けており母系によっても公家化が進んでいった。