さんじゅうきょうだいじゃなかったです
三従兄弟じゃなかったです
sanjū kyōdaijanakattadesu

Noun
Desu Copula

The polite, past negative form of みいとこ

1. Wasn't a third cousin.; Wasn't related as a third cousin.

Past/Perfective
Negative
Polite
Casual Register
Usually Written in Kana