Lord Manderly told me when I landed at White Harbor. Have you had any word of your sisters?
There was a letter, Robb said, scratching his direwolf under the jaw. "One for you as well, but it came to Winterfell with mine." He went to the table, rummaged among some maps and papers, and returned with a crumpled parchment. "This is the one she wrote me, I never thought to bring yours."
Something in Robb's tone troubled her. She smoothed out the paper and read. Concern gave way to disbelief, then to anger, and lastly to fear. "This is Cersei's letter, not your sister's," she said when she was done. "The real message is in what Sansa does not say. All this about how kindly and gently the Lannisters are treating her... I know the sound of a threat, even whispered. They have Sansa hostage, and they mean to keep her."
There's no mention of Arya, Robb pointed out, miserable.
No. Catelyn did not want to think what that might mean, not now, not here.
I had hoped... if you still held the Imp, a trade of hostages... He took Sansa's letter and crumpled it in his fist, and she could tell from the way he did it that it was not the first time.