Well, one possibility could be that the kids from the future come back to prevent a great disaster in the present. Maybe a dark wizard that was defeated in their time has somehow found a way to be reborn in the past (the present in the story), and they need to stop it before it's too late.
One possible plot could be that the child from the future comes back to prevent a great disaster. Maybe a dark wizard in their future time has found a way to rewrite history and the child has to make sure Harry and Ginny meet and fall in love at the right time. The child might also have some special powers inherited from their parents which they use to face various challenges in the past.
One option could be time - travelers from a different future. Maybe there are some wizards from a parallel future who want to change the past to suit their own needs. They might be opposed to Harry and Ginny's kids because they are trying to protect the original timeline. These antagonists could use some really complex time - magic to try and outwit the kids.
Well, it could be about Harry and Ginny teaching their kids magic. Maybe they have a child who struggles with a particular spell, and they have to find creative ways to help.
One possible plot could be that one of their kids gets a mysterious fever that no magic can immediately cure. Ginny and Harry are worried sick and start to search for a solution. They might visit old friends like Hermione for help, who uses her vast knowledge to look into ancient spells or potions.
Well, one possible plot could be that the kids start showing signs of magic very early and Harry and Ginny have to figure out how to guide them properly. Maybe one of the kids has a really powerful and unique magical ability that attracts unwanted attention from dark forces.
It's possible that when they meet their kids, they realize that their family has a special destiny in the wizarding world. Their kids could be the key to uniting different magical communities or solving an ancient mystery. This could lead to a series of adventures where Harry and Ginny, along with their kids, embark on a journey to fulfill this destiny.
One possible plot could be that they see a future where the wizarding world is in great danger again. So they start to train young wizards secretly to prepare for the upcoming threat.
Another theme could be the passing on of values. Harry and Ginny would want to instill in their kids the values they hold dear, like courage and loyalty. This can be shown through various interactions and situations in the fanfiction.
One possible reason could be a misunderstanding. Maybe Ginny misinterprets something Harry does and feels she can't stay in the relationship. Another reason might be that she feels overshadowed by Harry's fame and the pressure of being part of the Potter family. It could also be that she has some personal goals or dreams that she realizes she can't pursue while being with Harry and taking care of the kids.
One possible reason could be that she is forced to for some dark magic related plot. Maybe an evil wizard has put a spell on her that makes her think she has to leave to protect them. Another reason might be that she feels suffocated in her life with Harry and the kids, longing for her old adventurous self and thus decides to abandon them to seek freedom.