Although the relationship between the fathers-in-law and adopted son-in-law was not necessary bad while Fuhito was alive, but after his death, Prince Nagaya conflicted with the four brothers over the title of FUJIWARA no Miyako, who was a daughter of Fuhito and the real mother of Emperor Shomu, and their confrontation heated up.
不比等の生前こそ、舅と娘婿の関係であって関係も決して悪いわけではなかったが、不比等の死後に不比等の娘で聖武天皇の生母藤原宮子の称号を巡って長屋王と四兄弟が対立すると、その対立が露になってきた。