The fanfiction might explore how the child copes with this situation too. Is the child aware of the reasons? Does the child try to reunite the parents? There are so many possible storylines that can branch out from this one simple premise of Pepper leaving Tony with a child.
Family is a very common theme. It often shows how Tony and Pepper build a family together and the joys and struggles that come with it. For example, they might deal with the child's first steps in the scientific world if they inherit Tony's talent.
In the fanfiction, Pepper could find out she's pregnant right before a major crisis that Tony has to deal with. She has to be strong on her own while he's away, and when he comes back, he realizes how much she has sacrificed. This leads to a deeper bond between them and a stronger determination to create a happy family.
One popular Tony and Pepper child fanfiction is 'The Stark Family Legacy'. It beautifully portrays their life as parents and the challenges they face raising their child. It shows how Tony's genius and Pepper's strong will combine to shape their family's future.
The story could also take a more dramatic turn. The child might develop some sort of special powers or abilities due to Tony's genes or the unique circumstances. This could attract the attention of new villains or other powerful entities, forcing Tony to not only protect his child but also the world from any potential threats that come as a result of the child's newfound powers.
In this fanfiction, Pepper might struggle a bit with the idea of being pregnant while Tony is constantly in the spotlight as Iron Man. She could worry about how their child will grow up in such a public environment. However, Tony reassures her that they can create a normal family life within their extraordinary circumstances.
One common theme is the anticipation of parenthood. Tony might be shown as both excited and nervous about becoming a father. He could be constantly thinking about how to keep Pepper and the baby safe, especially considering his dangerous lifestyle as Iron Man.
The relationship could develop gradually. Peter would show his gratitude towards Tony and Pepper for taking him in. Tony would see Peter as not just a protege but also as a son. He would share his knowledge and experiences with Peter. Pepper would be involved in Peter's daily life, making sure he has everything he needs. For instance, she might cook his favorite meals or help him with his schoolwork. As they go through various challenges together, their bond would strengthen.
Yes, there are quite a few. You can start by looking on fanfiction.net. There are stories that explore their married life in different scenarios, like dealing with superhero duties while maintaining a family life.
I'm not sure if there is truly 'good' fanfiction in this regard as it goes against the general positive relationship depicted in the main story. Fanfiction often contains a wide range of interpretations, but this particular theme might not be in line with what most fans expect from the Pepper - Tony relationship.