I'm currently reading a book that is set in
Paris after WWI.
The mom is
Sandrine and the sisters are Jadine,
Opaline and
Delphine. Brother is
Sebastian.
I've never head of Jadine. It's a user-submitted name, stating that it's a feminization of
Jaden or an elaboration of
Jade.
It doesn't seem like the author did a lot of research and could easily have made up the name, but I was curious.