On this point, it seems appropriate to judge that she was Mototaka's (born in 1075) daughter, because it is not logical from a chronological point of view that Ienori's (born in 1048) daughter served as a nyobo for Bifukumonin (born in 1117) and gave birth to Chikamune (born in 1144).
これについては、家範（1048年生まれ）の娘が美福門院（1117年生まれ）に女房として仕え、親宗（1144年生まれ）を産んだとするのは年代的に合わないため、基隆（1075年生まれ）の娘とするのが妥当と思われる。