Toshimasa had married a daughter of the Mizuno clan, but did not have good relationship with the Mizuno family or the Matsudaira family after her death, and he strengthened relations with the Mizuno clan in his struggle against the Matsudaira family.
俊勝は元々水野氏の女性を妻に迎えていたが、その妻の死後に水野家と松平家の間で帰趨が定まらず、松平氏との対抗上その関係強化が理由と考えられる。