Anastasia Griffith is listed in the credits of episode 18 as Kathryn/Abigail. Perhaps Kathryn's not dead after all. The heart must belong to someone else.
That is somewhat of a relief. But the writers did say the whole Kathryn storyline would be wrapped up this season.
I listened to Once and fan podcast this morning and I’m going to list who I hope the heart DOESN’T belong to:
Henry, Jr. — that would be just really creepy of Regina if she somehow had little Henry’s heart
David — I can’t think of how this would work. I think it would make more sense if David was missing his brain than his heart 😆
Snow — because the Evil Queen never got her heart.
I heard Colleen say it on the fan podcast and I think the heart belongs to Henry, Sr. It would make a lot of sense. But then what about MM’s fingerprints on the box? I think those are fake, planted there by the curse.