One idea could be that their daughter discovers she has a unique ice - power ability like Elsa. She tries to hide it at first, afraid of being different. But then, she uses it to save the kingdom from a new threat. Maybe a group of bandits or a strange magical curse. This would lead to her own journey of self - discovery and acceptance, just like Anna and Elsa's stories in the original movie.
A possible plot is that the daughter, let's call her Isla, wants to explore the world beyond Arendelle. Kristoff is hesitant as he worries about her safety. Anna, on the other hand, encourages her. Isla then sets off on an adventure and meets new friends, some of whom are from other kingdoms with different cultures. Along the way, she has to use her wits and the skills she learned from her parents to overcome various obstacles. For example, she might use her father's knowledge of the mountains to climb a dangerous peak or her mother's charm to negotiate with difficult people.
The Duke of Weselton's nephew could be an antagonist. He might hold a grudge against Arendelle for what happened to his uncle. So he tries to undermine the stability of Arendelle by causing trouble for Anna and Kristoff's daughter. He could spread false rumors about her or try to sabotage important events in the kingdom.
One possible plot could be that Anna and Kristoff go on a journey to find a magical flower that is said to have the power to heal any ailment in the Enchanted Forest. Along the way, they face various challenges like wild animals and difficult terrains. They also have to deal with their own relationship issues as the stress of the journey tests their love for each other.
One possible plot could be that Anna discovers she's pregnant and she and Kristoff are overjoyed. But then they face challenges like how to keep Anna safe during her pregnancy in the sometimes - dangerous world of Arendelle. They might also worry about how to raise the child with all the responsibilities of ruling the kingdom.
One possible plot could be that they have a small, intimate wedding in the forest. All their friends from Arendelle and the trolls are there. Anna might wear a simple yet elegant dress made by the local seamstresses in Arendelle. Kristoff would be all nervous but excited at the same time. During the ceremony, they exchange heartfelt vows about their journey together and how they will support each other through everything. And after the wedding, they go on a short honeymoon to a nearby secluded valley where they enjoy the beauty of nature together.
In a fanfic about their wedding, there could be an event where the rings go missing. Everyone starts to panic and search everywhere. It turns out that a little mischievous sprite had taken them, thinking they were shiny toys. Anna and Kristoff have to convince the sprite to give them back. Also, during the reception, a competition could be held between the townspeople and the forest dwellers to see who can perform the best wedding - themed skit. This brings the two communities closer together and adds a lot of fun and laughter to the wedding.
One possible plot could be the challenges they face as new parents. Maybe Kristoff is worried about providing for the family while still being part of the ice - trading business. Anna, on the other hand, might be struggling with the balance between her royal duties and taking care of the baby. They could also have an adventure where they have to protect their baby from some sort of threat in the magical world they live in.
One possible plot could be that they face challenges in adjusting to their new life as parents. Maybe they struggle with sleepless nights and learning how to take care of the baby. Kristoff might use his skills from living in the mountains to build a special crib or play area for the baby. Anna, on the other hand, would be the loving and nurturing mother, singing lullabies she learned from the castle.
Anna and Kristoff's wedding was a grand affair. The whole of Arendelle was decorated with ice sculptures and flowers. Anna looked stunning in her white dress, with a tiara on her head. Kristoff was dashing in his suit. As they exchanged vows, there was not a dry eye in the crowd. Sven was there too, with a little flower crown on his antlers. After the ceremony, they had a huge feast and danced the night away, their love finally sealed in marriage.
One plot idea could be them preparing for the baby. They might face challenges like finding a suitable place to raise the child in Arendelle. Kristoff could be worried about how to be a good father, while Anna is excited to start a family. They could also have some cute moments like choosing baby names together.
The build - up to the kiss can be really interesting. For example, if the author creates a lot of tension between Anna and Kristoff before they kiss, like misunderstandings or challenges they have to overcome.