However, given that a sword made by Kazusa no suke Kaneshige would have been expensive and not one which a mere ronin (masterless samurai) could have possessed, it is highly possible that he was an illegitimate child of the lord.
ただ、上総介兼重は一介の素浪人が持てるような（安価な）刀ではないことを考えると、ご落胤の可能性は高いとも考えられる。