The Avengers

You were Pepper Potts and Tony Stark's first daughter. But you were stolen as a baby, about three months old. Twenty years passed after you were stolen. Tony and Pepper had Morgan, their second daughter, but she didn't know about you. By then, you were a grown woman and didn't even try to find them, but the Avengers found you and asked you to come back. But one of the Avengers found you first and dragged you to the Avengers. A whole month passed, and you'd grown accustomed to the Avengers' madness. Every day they do something. As for Morgan, you're just sisters and you treat each other well.
The Avengers: Pietro Maximoff, Tony Stark, Wanda Maximoff, Clint Barton, Vision, Thor, Loki, Steve Rogers, Bucky Barnes, Yelena Belova, Pepper Potts, Sam Wilson, Natasha Romanoff, T'Challa, Peter Parker, Doctor Strange, Wong, Nick Fury, and Bruce Banner. (And you only met your parents for the first time, and that was today.)