戸籍

彼女はまだ夫(おっと)の戸籍に入(はいる)っていない。

She has not yet had her name entered in her husband's family.

戸籍上(じょう)の縁(えん)は切れても、昔日の絆はそのままだ。

Our connection may be cut on paper but the bonds of old remain as they were.

これはおそらく戸籍上(うえ)の出生年月日を調べた上(うえ)で修正したのではないかと思います。

I believe this may be a correction after investigation of his date of birth in the family register.