There is a moment when Susan thinks it might go either way, when she is caught between the Lion and her brother and does not know which was it will go. And then Aslan laughs -- laughs! -- a deep rumble and says, "Very well, Son of Adam. Very well, Daughter of Eve. Narnia will rejoice to have you again, but England will mourn, and your brother and sister will bear a great burden there. Will you help them bear it?"

(I don't know how this AU ends but I kind of hope it involves Caspian spending some time in our world, walking upside down on the bottom of the globe)