I think it's very funny that in Game of Thrones Catlyn gets a coded letter from Lysa, because you might assume it's in some kind of Westerosi Pig Latin, but if you've ever spoken to teenage girls you'll know that they just use ridiculous nicknames and weird references. There's a chance what the note actually said was:
"Goldilocks Cece and Uncle Blackfish's fanboy mothered Old J, stay Frey" instead of "Queen Cersei and Jamie killed Jon Arryn, be cautious"
I've been listening to the (always excellent) @radiowesteros series on Arya Stark and something occurred to me. Before Arya, Gendry and Hot Pie were taken to Harrenhal, they spent some time living in the wilderness. While there, they met a clearly traumatised woman and a little girl. The woman died after a few days, and the little girl ran off and is never seen/heard from again. It seems like an odd detail to mention, aside from showing more of the small folks' suffering.
So i was wondering if the little girl is Jaquen Hagaar in disguise. He needs to keep tabs on Arya, possibly because she owes the many-face god a life debt, possibly because he's come to Westeros to recruit her. Obviously, he's able to disguise himself pretty efficiently! Most of this argument comes down to that joke about Batman: weird how you never see Bruce Wayne and Batman in the same room, or, weird how you never see Jaquen Hagaar and this little girl together. Also, there's the traumatised woman. She certainly could be in a state of shock because her home burned down, she witnessed mass execution or, GRRM's favourite, SA. However, it's also possible that she saw an adult man turn into a little girl and doesn't know how to process that. The woman does die pretty quickly, possibly because of a conveniently-located assassin?