Saga already had a son with Takatsu called Imperial Prince Nariyoshi, but Nariyoshi had a severe physical and mental congenital disability and was considered to have no possibility of attaining the throne.
嵯峨にはすでに高津との間に生まれた皇子業良親王がいたが、業良は先天的に心身に重篤な障碍を負っており、皇位継承は不可能とみなされていた。