Sugen-in loved Tadanaga whom she raised by herself more than Iemitsu who was reared by menoto (wet nurse) Kasuga no Tsubone and some backed up Tadanaga as an heir.
崇源院は乳母春日局に養育された家光よりも、自ら育てた忠長を溺愛したとされ、忠長を継嗣に推す者もあったと言われる。