Board Thread:General Discussion/@comment-5106672-20140324015542/@comment-1293767-20140328010153

Neal: The symbol of Emma's heart. (And he's already missing. I also wonder if this tied into the reason they wanted Graham back for the Oz storyline.)

Henry: The symbol of Regina's heart.

Snow's baby: The symbol of Snow's heart?

I think one of the first two are more likely though.