Yoshihisa Tokugawa is one of the three names that Prince Iesato Tokugawa's son went by. Besides going by the name Yoshihisa Tokugawa, he also went by the names Iemasa Tokugawa and Iyemasa Tokugawa. The wikipedia page for Iesato Tokugawa presents a family photo with Iesato and his son seated together, along with Iesato's wife and his three daughters. The press caption for that photo identifies Iesato's son being named Iyemasa Tokugawa. The wikimedia photos currently labelled as being Yoshihisa Tokugawa, is the same individual that is identified as Iyemasa Tokugawa in the Iesato Tokugawa family photo.
One other important item, many current internet historical sources say that Yoshihisa Tokugawa is the father of Princess Kikuko Takamatsu (the wife of Prince Takamatsu, the brother of Emperor Hirohito). However, Iesato's son is not the father of Princess Kikuko Takamatsu. It isn't clear who her father was. Some internet accounts say that Princess Kikuko Takamatsu's father was an individual named Yoshihisa Tokugawa who was the 7th son of Shogun Yoshinobu. There is limited information about Princess Kikuko Takamatsu's father. Most historical accounts say Princess Kikuko Takamatsu's was the grand-daughter of Shogun Yoshinobu. Prince Iesato Tokugawa was the adopted son of Shogun Yoshinobu, and that would make him Princess Takamatsu's uncle, and Iyemasa Tokugawa would be her older first cousin.
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↑The Art of Peace, an illustrated biography about Prince Iesato Tokugawa
{{Information |Description={{en|Yoshihisa Tokugawa}}{{ja|徳川慶久}} |Source={{en|Japanese book "Kazoku Gaho (Pictorial Peerage of the Empire of Japan)" published by Kazoku Gaho Sha.}}{{ja|華族画報社「華族画報」より。}} |Date={{en|Octo...