Mother, I...!

Stella: ......
Lucina: Beg pardon, mother. Might I have a word?
Stella: ...Lucina. What is it?
Lucina: It's about Father. I have memories of him, you know. From when I was little. Before he...died.
Stella: I see...
Lucina: He was courageous, and kind, and everyone spoke fondly of him. People say he was brave up until the very end. I always yearned to know him better. And now that I do...I can see the world will be robbed of a very great man. ...I won't allow that to happen.
Stella: I understand. You love him. ...As do I.
Lucina: Mother, I...Please, forgive me...
(Lucina points the Falchion at Stella)
Stella: Lucina?!
Lucina: Stay where you are, Mother! I have no choice. I must kill you.
Stella: What?! What madness is this?!
Lucina: In my future, you...You kill father.
Stella: No! That's insane! Why would I kill Chrom?
Lucina: I was not certain myself, until now...I knew he had been killed by his closest friend. Having witnessed your bond, I doubted it could be so...But today's events make it clear. You are at Validar's mercy. I suspect it's he who forces you to take Father's life, and very soon...
Stella: Lucina, wait.
Lucina: If Father is right, then we can change our fates. If this dark future is to be averted, sacrifices must be made. I am sorry, Stella! I know this is matricide, I...I know that...
Stella: Lucina, you don't have to—
Lucina: Don't make it harder! It...will be swift and painless. If you hold any love for Chrom, then let this be done...

(Accept Lucina's judgment?)
YES:
Stella: ......My life is yours. It always has been.
Lucina: D-don't say that, Mother! Don't! That...only makes it harder.
Stella: I would give my life for Chrom. ...And for you.
Lucina: Mother, please...
Stella: I know you will be quick about it. I love you, Lucina.
Lucina: M-Mother...
Stella: ...I'm ready. Do what you must.
Lucina: I... I...
Stella: ......
Lucina: Damn me! I can't do it! I love you too much! I'm sorry, Mother. I'm so sorry! P-please forgive me!

NO:
Stella: ......I love him as much as you, Lucina. But you ask too much.
Lucina: Perhaps I do...Then draw your weapon, and we will let combat pass the final judgment!
Stella: I would rather die than point a blade at my own daughter.
Lucina: Mother, he's going to DIE! Something must be done!
Stella: Lucina, you and Chrom and I are family. And you only get one of those. We are going to stay together, and we are going to survive!
Lucina: That's all I want! But...
Stella: Lucina?
Lucina: Ah, gods! I can't do it! I'm sorry, Mother. I'm so sorry! P-please forgive me!

(either way...)
Stella: My poor girl...there's nothing to forgive.
(Chrom enters the scene.)
Chrom: Are you done, Lucina?
Lucina: Father! I... I can explain!
Chrom: No need. You're not the only one who can eavesdrop. I heard every word. Lucina, I know your heart is in the right place...But I trust Stella. You cannot shake my faith in her. Stella and I have held fast through good times and ill...We swore to be two halves of a greater whole. You underestimate the strength of those ties, the bonds we share. I believe in them more than some foretold "destiny."
Lucina: This is easier to say when you haven't seen it yourself...
Chrom: Lucina, aren't our ties stronger now than they were in your future? You said so yourself. In this flow of time we are bound tighter than ever, you and I. Not just as father and daughter...But as friends. We can change things—we already have...and we will again.
Lucina: ...Very well, Father. Mother, I...I hope someday you will find it in your heart to forgive me...And I pray... That is, I trust the both of you will prove me wrong. That the future will crack and fall apart before our family bond ever does.