Where did I say brother? Did I make a typo? Shit. *goes to check*

Okay, the thing with Jack and Claire...as we found out last season, they are half-siblings. Christian, Jack's dad had an affair with an Australian woman (Claire's mom). They however don't know this on the show yet, but since this is a bit into the future, they know in my story.

Does that help at all? (Sorry this is so confusing, it wasn't meant to be)