With bandages still fresh from the barbed needles from his sister, Kaito waits until she is gone for the day, and then using methods only known to littler brothers throughout the world, infiltrates her room. He took a few rocks from a bag, and slid them in between the mattress and box spring of the bed. Satisfied with that for now, he exits the room the same way he entered.
Back to his own room, Kaito gathers his things, and leaves the house with a note explaining he was going camping. When one was at war, you didn't leave yourself open to attack, and out in the woods where he could sleep in a different place every night was more secure then his room. It didn't take him long to arrive deep in the woods, and he goes to one of his normal places, stashing his backpack and supplies. That done, he heads back into town, to talk to the post office. People seriously underestimated how easy it was to find someone if you just asked....