Her father Tadamasa also held a territory in Mikawa Province near Ogawa, and upon the request of Kiyoyasu MATSUDAIRA who held a great deal of power in Mikawa at the time, he made Otomi no Kata divorce and marry Kiyoyasu but his desire to further strengthen his relationship with the Matsudaira clan led him to marry off his daughter Odai in 1541 to Hirotada MATSUDAIRA who succeeded Kiyoyasu.
父・忠政は緒川からほど近い三河国にも所領を持っており、当時三河で勢力を振るっていた松平清康の求めに応じて於富の方を離縁して清康に嫁がせたが、松平氏とさらに友好関係を深めようと考え、天文10年（1541年）に娘の於大を清康の後を継いだ松平広忠に嫁がせた。