He had brothers including the 15th lord of the domain Mochinaga TOKUGAWA (Mochiharu, the 11th Hitotsubashi Tokugawa family), the lord of the Aizu Domain Katamori MATSUDAIRA, the lord of the Kuwana Domain Sadaaki MATSUDAIRA and they were called Takasu Four Brothers including Yoshikatsu himself.
兄弟に15代藩主徳川茂徳（一橋徳川家11代茂栄(もちはる)）、会津藩主松平容保（まつだいら・かたもり）、桑名藩主松平定敬（まつだいら・さだあき）などがあり、慶勝を含めて高須四兄弟と併称される。