FUJIWARA no Yorimichi's father, FUJIWARA no Michinaga, also favored Morofusa and made one of his daughters Morufusa's wife; furthermore, Michinaga is believed to have said that if no sons were born to FUJIWARA no Yorimichi he would let Morofusa change his surname to FUJIWARA and become a member of the sekke (line of regents and advisers).
藤原頼通の父・藤原道長も師房を寵愛して娘を嫁がせた上に藤原頼通に男子が生まれなければ、師房を藤原氏に改姓させて摂家を相続させても構わないと言ったとされている。