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.
As a consequence of her relationship with an enigmatic man (Isamu Noguchi biographer Masayo Duus proposes that he may have been one of Léonie's students), Léonie became pregnant and gave birth to a daughter, Ailes Gilmour in 1912.