It's Not That Easy - Tumblr Posts

Um guys… Cassie specifically said “Cutting the Parabatai rune doesn’t break the bond. That’s why they have a whole ritual/parabatai ceremony that has its own magic. Because a rune can be cut in battle, or you could lose that limb that was runed, etc. They wouldn’t consider you not parabatai any more, and they’d re-rune you, but in the meantime the magic of the ritual would keep the bond from breaking. Your parabatai might feel it, or might not, but it wouldn’t be what happened to Will in CP2. Things that sever the bond: Exile (Robert and Michael) someone becoming a Silent Brother or Iron Sister (Jem and Will) death (Silas and Eloisa) someone becoming a Downworlder (Luke and Valentine) or anyone becoming a mundane/having their Marks stripped.” http://cassandraclare.tumblr.com/post/100638410099/the-runes-can-have-their-effect-cut-off-that

Wow the answers been staring us in the face the whole time!!