>>104143508Nadia took the Van Dyne last name because she found out that her father hit Jan once (Jan never mentioned that she knew that Hank was unstable and still took the opportunity to marry him) and well... Jan also never mentioned that Hank is merged with Ultron and practically forbade everyone in the super heroic community from telling Nadia about that.
Jan is being a bitch, in the last issue Nadia asked Jarvis if he knew anything about her father and why AIM thinks he will kill them all... he lied to her because of Jan.