Oh man, that could make sense. Could by why dumb Ned never would tell anyone about where John was from other than that John was his bastard. Would make sense if that was his sis's kid and had to hide the fact that John is half targaryn since that would have been right after the revolt and all other targaryn kids were thought to be murdered at that time. Keep lil sis's kid safe by claiming him as Dumb Ned's own. Man.
I just moved on to other books and didn't take the time to think through much stuff like this.
Damn that next book needs to come out.