Ya it's definitely the orphan children. There's many hints pointing at that. Bran had already decided he didn't want to go into the farm, and Osha (the wildling) was talking about climbing trees so I'm guessing she climbed over, stole some food, maybe dropped a walnut or something stupid, then climbed back and they continued. And now Theon is just an asshole and needs to be killed. Time to continue reading the second book, it's most definitely much longer than the show.