[If it has anything to do with those paths - the ones his father wrote about, and the ones he saw when he kissed Historia - then, as far as Eren understands it, Caitlyn would have to be Eldian. That still isn't impossible, but there exists a clear disconnect. They need to figure out how deep it runs...]

Let me ask you something.

How likely do you think it is you and I are from the same place?

You didn't know that word - Eldian. That's strange.