One interesting plot could be that Harry, Ginny and Teddy travel back to the time when the Marauders were at Hogwarts. They could interact with James, Sirius, Remus and Peter, and maybe even change some small events that have a big impact later. For example, they could prevent Peter from becoming a Death Eater spy, which would change the course of the war against Voldemort.
Teddy, being a young character, would grow up very quickly in a time - travel story. He'd learn about the great sacrifices made by his family and the importance of loyalty. He could also develop new magical abilities by being exposed to different magical teachings from different eras. His character would transform from a somewhat naive young boy to a more mature and capable wizard, with a much broader view of the wizarding world.
Luna Lovegood would be a great addition. Her unique perspective on magic could offer new insights to Teddy. Also, Ron could be included as Harry's best friend. His humorous and sometimes clumsy nature could add some light - hearted moments to the story.
One challenge could be the Time - Turner rules. If they are using a Time - Turner, they need to be very careful not to break any of the laws regarding time travel. For example, they can't be seen by their past selves or make significant changes that would disrupt the future they come from. Another challenge is the danger of the time period they visit. If they go to a time when Voldemort was active, they are at great risk of being detected by Death Eaters.
Another idea is that they travel to a time just after the end of the First Wizarding War. There is chaos and rebuilding going on. Harry and Teddy could be on a mission to retrieve a powerful magical artifact that was lost during the war. Along the way, they meet survivors of the war and learn about the true cost of the conflict. Teddy, who has grown up in a post - Voldemort world, is deeply affected by the stories of those who lived through the dark times.
In the fanfiction, their relationship would be constantly evolving. At first, they might face some challenges as they adjust to having a child in their lives. But as they grow into their roles as Teddy's guardians, they would rely on each other more. They would have late - night conversations about Teddy's future, and these deep discussions would strengthen their emotional connection. Their relationship would no longer just be about themselves but also about the family they are building with Teddy.
In this fanfiction, perhaps Harry and Ginny would teach Teddy all about his parents. They might share stories of Remus and Tonks with him. Teddy could grow up in a loving environment filled with magic and family values.
Maybe at first Teddy is a bit shy and reserved, but as Harry and Ginny show him love and support, he begins to open up. They could also have some challenges like dealing with Teddy's occasional magical outbursts that come with his young age and powerful magic inheritance. Harry, having been through so much himself, can be a great mentor to Teddy in controlling his magic.
Well, in the 'Harry and Ginny raise Teddy' fanfiction, they could face some challenges too. For example, Teddy being Remus and Tonks' son might have some unique magical traits that are difficult to handle at times. But Harry and Ginny, with their own experiences of dealing with difficult situations in the wizarding world, would be able to overcome these. They might also introduce Teddy to their friends and family, like the Weasleys, creating a big and loving social circle for him.
One possible plotline is Teddy's education. Harry and Ginny could be very involved in Teddy's magical education. They might encourage him to study different branches of magic, like Transfiguration or Potions. Another plotline could be Teddy's relationship with his godfather, Harry. Since Harry is like a father figure to Teddy, their bond could be explored, such as how Harry imparts his values to Teddy.