There's a part in this game where you meet this lamb that's sick. The shepherd that is caring for it says it's not going to survive, and her attempts to heal it have failed. You know you have a healing spell, you can even hear the notes you need to cast in her song, but you aren't strong enough yet, so you have to leave, and by the time you are experienced enough to cast that spell it's too late to do anything.

That's essentially the whole game. I loved it a lot.