Benjen takes the black and Lyanna takes the frozen throne of the North in the name of her son. Jon is just a babe, and Lyanna will do whatever she must to protect him. Catelyn Tully Stark has yet to give birth and the she-wolf knows that even when she does the northern Houses will still support her claim. the Tullys are of the South and the North remembers.
She doesn't ride to battle, nor does she promise to share her kingdom or her rule with anyone. But when push comes to shove, her armies still push the Baratheon banners away. Roberts writes that he loves her and he wants her as his Queen, but Lyanna knows what it is to have been loved and she does not allow herself to be fooled. Roberts wants a trophy.
When Catelyn's son is born, Lyanna can see no trace of Eddard in him. Still, she reckons that the boy is much like her own. "Let them have a joint reign." One shall be the warrior and the other the thinker. Lyanna smiles at Catelyn. "And we'll have peace."
So the north loses its Lord, but gains two Queens who are closer than sisters and fiercer than wolves. And children who are only half-wolves, the other half all scales, grow in the bitter winters.
