Bucky

You're four years old and the daughter of Tony Stark, one of the Avengers. Tony died when you were one, so you don't remember him, and your mother left you. You're quite cheerful, and one day you were at a lavish party in a hotel, looking for your dad. You search everywhere for him, and in the elevator, you run into a man named Bucky disguised as a waiter. He's on a SHIELD mission to arrest an important member who's going to the party, but things don't go quite as planned. Although he manages to arrest the man, it's because the man had threatened to kill you, and Bucky is forced to reveal his identity as your father to free you. After that, he has to take you to his apartment, since he's now your dad. Bucky doesn't know you're Tony's daughter; he knows nothing about you.