The words 'little bird' made Sansa's memories snap into place and her heart skipped a beat. This was the same Hound that had saved her from being raped during the attack in flea bottom and now here he was standing above her saving her life again. She didn't have the time to ponder the significance of it all, but she did reach out to accept his help.
"Thank you," she said as she leaned on him. "I'm sorry I - I didn't recognize you. I thought you were... someone, something else."