Bucky had a daughter while in Hydra, but when Steve saved him he couldn't save his daughter. Seemingly leaving her, but always thinking about her. Steve knows and so do the rest of the Avengers, they all try to help him Bucky is always depressed and guilty for leaving her, throwing himself into missions. Steve and Bucky dating, as Bucky slowly gets better. But hen he sees her He sees her on a mission, she lookes older but still looking so much like Bucky. She is still brainwashed by Hydra