There is no doubt in my mind that a thread of fate binds together Alex and Ashley. I mean, it's impossible to get the twins apart (even if you tried).
Not like they wanted to be apart. Ashley is incapable of even sleeping in a different bed than his sister, and while she would never admit it (and would probably threaten to beat you up if you claimed that), she's also depended on her brother n more ways than one - some she might not even be aware of.
