It seems that this marriage was against her father Motohiro's will and Hiroko got married after she was adopted as a daughter of Tokitsune HIRAMATSU who was Monyo (blood line) of the Konoe family.
父・基熙にとってこの結婚は不本意な物であったらしく、熙子は近衛家の門葉である平松時庸の養女となって嫁した。