Another theme is change. Arthur's life changes drastically when his partner is pregnant. His daily routine, his relationships, and his own self - perception all shift. For example, he might become more responsible and caring.
Support is also a big theme. The fanfiction often shows how Arthur's friends and family support him during this time. It could be his best friend helping him prepare the nursery or his parents giving him advice on being a good father.
The theme of family and legacy often comes up. Arthur, being from the Weasley family, has a certain legacy. Hermione, coming from the Muggle - born world, also has her own values. The pregnancy makes them think about the kind of family they want to create. There are also themes related to magic and how it can be used to ensure a healthy pregnancy in the wizarding context, like special spells for prenatal care.
Another theme is the exploration of their different personalities. Arthur is usually more responsible and DW can be more carefree. Fanfictions play with this by putting them in situations where their personalities clash at first but then they find a way to complement each other. For instance, in a story where they are planning a party for their parents, their different approaches initially cause problems but in the end lead to a great celebration.
One of the themes is leadership. Since Arthur is a king, many fanfictions explore how Gwen influences his leadership style and vice versa. They are often depicted as a power couple, making decisions together for the betterment of their people. Also, the theme of sacrifice is present in some fanfictions. Either Arthur or Gwen might sacrifice something for the other's well - being or for the good of the kingdom.
One common theme is the struggle between good and evil within their relationship. Since Morgana often turns to the dark side, it's about how Arthur tries to bring her back or how their relationship is affected. Another theme is love, either a forbidden love or a love that could have been if circumstances were different.
One common theme is mentorship. Arthur often takes on a mentorship role for Harry, guiding him in the wizarding world. Another is family. Since Harry lacks a proper family, Arthur can represent a father - like figure in these stories.
One common theme is friendship. Their relationship is often at the heart of the stories, showing how they support and grow with each other. Another is loyalty. Arthur and Merlin are extremely loyal to each other in the original series, and this is often emphasized in fanfiction.
School - related themes are also popular. This can include things like preparing for a school play, dealing with a strict teacher, or competing in a school competition. These themes allow for a lot of interaction between the two characters and often show how they rely on each other's strengths to get through difficult situations.
One common theme is loyalty. Since they are brothers, their loyalty to each other is often a central focus. They will go to great lengths to protect one another.
There are also fanfictions that focus on the emotional bond between them. It could be a deep, almost father - son like bond that is slowly eroded by events. Or it could be a more complex, codependent relationship where they both rely on each other in different ways for different reasons. And sometimes, the theme of redemption can come into play, especially if one of them has wronged the other and is trying to make amends.
Friendship is a very common theme. The stories often show Arthur and the squirrel forming an unlikely friendship and learning from each other.