Ultimately there’s an echo of what Lily did, quite a conscience echo, right at the start of the story, at the very end of the story. At the start of the story Lily dies to keep her son alive. At the end of the story Harry lies to be pretending to be dead on the ground and it’s a mother who saves him again because she’s trying to get to her own son. That was closing a circle. He was saved by Lily and saved by Narcissa.

“I have spied for you, and lied for you, put myself in mortal danger for you. Everything was supposed to be to keep Lily Potter’s son safe. Now you tell me you have been raising him like a pig for slaughter -“

She had a way of seeing the beauty in others, even, and perhaps most especially, when that person couldn’t see it in themselves. Your father, James, however, had a certain, shall we say, talent for trouble. A talent, rumor has it, he passed onto you. You’re more like them then you know, Harry. In time you’ll come to see just how much.