Her attention stayed locked onto Nathan, her scowl fierce. It faltered slightly when Luke offered her the cookie. She offered the boy a shy smile of thanks, but then immediately turned back to glare at the man that had dared upset Peter in such a fashion. She didn't stop glaring until Peter intervened.
Anyone else may have argued with his logic. After all, he was a grown man and if he wanted to leave, it was his business to do so. However, Annie wasn't capable of that level of thought. All that she knew was that Nathan wasn't being a good brother. But Peter said it was okay, so she stopped glaring and simply said softly, "Be. Nice."
Considering the conversation over and done with, as far as she was concerned, she twisted around so she could look at Peter. Her smile brightened as she held up the treat that Luke had given her.
"Cookie!" she announced in a matter-of-fact tone. Then her gaze flickered briefly to Hiro and, as though just realizing a new person was there that she Did Not Know, her hands instantly moved to cover her face, the cookie hovering in the air in front of her in lieu of falling to the floor.