Another approach could be to introduce a conflict within their relationship. Maybe Natsu accidentally uses his magic in a way that endangers Wendy. This causes a rift between them, but as they work through the issue, they come to understand each other better. Wendy realizes Natsu's impulsive nature sometimes gets the better of him, and Natsu learns to be more careful around Wendy because of her more fragile nature.
Their relationship can be developed by having them share more personal stories about their past with the dragons. For example, Natsu could tell Wendy about Igneel's funny habits, and Wendy could share her memories of Grandeeney. This would strengthen their bond as siblings who share a common dragon - slayer heritage.
One way is to put them in a life - threatening situation where they have to rely solely on each other. Let's say they are trapped in a magical maze with deadly traps. Natsu's strength and Wendy's healing and support magic would be crucial. Through this experience, they would learn to trust and depend on each other more deeply, further developing their relationship.
Perhaps a plot where Natsu and Wendy are transported to a parallel world where their roles as dragon slayers are completely different. In this world, they are the only hope against an evil dragon that has enslaved all the other dragon slayers. They must quickly adapt to this new reality and use their sibling bond to figure out how to defeat the dragon.
In this fanfiction, for the relationship between Natsu and other characters, Natsu's new Alph Dragon Slayer powers could attract the attention of villains. This would make his friends more protective of him. For instance, Wendy could use her healing magic to help Natsu when he gets injured during battles against enemies interested in his powers. Natsu could also form new friendships with characters who are also interested in the secrets of the Alph Dragon Slayer magic. They could exchange knowledge and experiences, which would in turn develop Natsu's character and his relationships with others.
They could have more deep conversations about their future as a family. For example, discussing how they want to raise their children, what kind of values they want to instill. Also, showing them supporting each other in small daily things, like Lucy helping Natsu with his reading skills and Natsu helping Lucy when she has a tough day at the guild. This would strengthen their bond on a more personal level.
Yes, in certain fanfictions Natsu and Wendy are considered siblings. This could be due to various reasons. Maybe the author wants to explore a different family dynamic within the Fairy Tail world. It can add an interesting layer to their relationship, like how they support each other more like family members would. Also, it might change the way they interact with other guild members as well.
One way is to put them in difficult situations where they have to rely on each other completely. For example, if they are trapped in a magical maze, they'll need to communicate well and trust one another to find the exit. Another is to introduce a new character who is interested in Peter romantically. This would make Wendy realize her true feelings for Peter and cause her to be more assertive in their relationship.
One way to develop their relationship further is through facing challenges together. Let's say there's a drought in Neverland and they have to find a way to bring water back. During this process, they rely on each other's strengths. Peter uses his flying skills to search for water sources from above, while Wendy uses her kindness and ability to communicate with the animals to find hidden springs. As they work together, they grow closer and start to understand each other on a deeper level. Also, they could have a bit of a misunderstanding, like Wendy thinking Peter doesn't care about her as much as she thought. But then they talk it out and their relationship becomes stronger because they learn how to communicate their feelings better.
One way is to focus on their shared adventures. For example, when they are on a quest for a new power source or to stop a new threat, they can rely on each other more. Goku can protect Bulma physically, while Bulma can use her intelligence to help Goku strategize. Another way is to explore their past more deeply. Maybe there are some untold stories from when they first met that can strengthen their bond.
Their relationship could be developed by having them face a difficult challenge together. For example, if Neverland was in danger of disappearing, they would have to rely on each other's strengths. Wendy's practical thinking and Peter's knowledge of Neverland's magic could combine to save the day. This would deepen their bond as they realize how much they need one another.
One way is to give them new shared challenges. For example, a powerful new villain comes to Neverland and they have to rely on each other's strengths more than ever. Their relationship can grow as they see different sides of each other while facing this threat. Another way is to explore their past more deeply. Maybe there were some unspoken words or moments between them that can be revisited and resolved, which would bring them closer.
Putting Wendy in a leadership role within the guild for a fanfiction story would be interesting. She could learn to be more assertive and make tough decisions, which would help her grow as a character. It would also show how she can inspire others in the guild.