The first time she falls asleep on him, they've just won a long and hard battle and they are all exhausted, but Ahsoka is only fourteen and not used to this. Anakin looks down at her, tiny and relaxed and too innocent for this war, and he silently vows to protect her with everything he has. She's his now, his Padawan, his little sister, and he'll never let anyone take her away from him.