In 1912 as a result of a relationship with a man whose identity remains mysterious (Isamu Noguchi biographer Masayo Duus speculates that he was one of Léonie's students) she gave birth to a daughter, Ailes Gilmour.
The birth of Ailes Gilmour in 1912 was a direct consequence of Léonie's romantic relationship with an unknown man (Isamu Noguchi biographer Masayo Duus suggests that he may have been one of her pupils).