At first, he might deny it. Tony is a complex character. But as evidence mounts, he'd have to accept it. He would then be determined to make up for lost time. He'd introduce her to his world of technology and science. He'd also be constantly on guard, making sure no one harms her. He might even start to see her as a chance to leave a different kind of legacy, not just through his inventions but through his family.
He'd probably be shocked at first. Tony is always so caught up in his own world that a secret daughter would be a huge surprise. But then he'd likely be protective. He might try to keep her away from his dangerous life at first, but as he gets to know her, he'd start to include her in things.
He would probably be overprotective at first. Tony has been through a lot, and the idea of his daughter having mutant powers, which could make her a target, would be scary for him. He might try to keep her locked away in the Stark Tower, but that would likely lead to her rebelling.
He'd be frantic. Tony loves his daughter deeply, so he'd immediately start searching for her. He'd use all his resources, his technology, and his connections to find her.
He would be extremely worried. Tony Stark, despite his tough exterior, loves his daughter deeply. He'd probably start by using all his resources to find her. He has access to advanced technology, so he'd likely use his Stark Industries gadgets to track her down.
One possible plot is that she inherits some of Tony's genius. She could start building her own high - tech gadgets in secret. But there are villains who learn about her existence and try to use her to get to Tony's technology. So, she has to fight them off while also trying to understand her father who she never really knew.
One interesting fanfiction could be where Tony Stark's secret identity is discovered by an ordinary citizen who then has to decide whether to expose him or protect him. This creates a whole new dynamic as Tony has to deal with this unexpected threat to his double life.
Another idea for this fanfiction could be that Tony Stark's daughter starts as a sort of 'Avengers - in - training'. She is constantly trying to prove herself to the established members. There could be a lot of action - packed scenes where she is in dangerous situations but manages to use her wits and any skills she has learned from her father to get out of them.
Love and friendship are also common themes. Her relationships with friends at school or in the superhero community, and her romantic interests if any, are often explored. It gives a more well - rounded view of her character as not just a Stark, but also a young girl growing up in a complex world.
One popular type of fanfiction could be about Tony Stark's daughter joining the Avengers. Maybe she inherits his genius and creates her own high - tech suit. She might struggle at first to be accepted by the existing Avengers, like Iron Man did. But through her skills and determination, she gradually wins them over and becomes an important part of the team.
Pepper Potts could be a common character. She might be in a position where she tries to mediate between Tony and his unwanted daughter, either trying to get Tony to be more accepting or helping the daughter understand Tony's perspective.
In a time travel fanfiction involving Morgan Stark, perhaps she travels back in time to a crucial moment in her father's life, like the battle of New York. She uses her knowledge from the future to help him, but also has to be careful not to disrupt the timeline too much. Morgan might end up forging a new bond with her father that was different from the one she had in her own time.