A prevalent theme is the exploration of Danny's past. Since he's in a younger state, it can be a chance to look at things that happened when he was younger in the context of the show. Also, the theme of adaptation is there. Danny has to adapt to his new body and abilities, and those around him have to adapt to the new Danny. There are often comical moments that come from this process of adaptation as well.
The theme of vulnerability is also quite common. As a deaged Danny, he may not have full control over his powers or be as physically strong as he was before. This makes him more vulnerable to his enemies. And often, there's a theme of growth. Despite being deaged, Danny still has to grow in some way, whether it's learning to control his powers again or dealing with new emotions.
One common theme is the idea of innocence regained. When Danny is deaged, he often has a more innocent view of the world, which contrasts with his normal teenage self who has seen a lot as a ghost hunter. Another theme is the change in relationships. His friends and family may have to take on different roles, like becoming protectors or caretakers.
Love and friendship are common themes. Their relationship, whether it's a budding romance or a deep platonic bond, is often explored.
One common theme is the struggle between good and evil within Danny. It often shows how his normal self battles his evil side. Another theme is the impact on his relationships. His friends and family have to deal with this new, dangerous Danny.
One common theme is family. Since they are siblings, a lot of fanfics explore their family bond, like how they rely on each other and protect one another. Another theme is secrecy. Danny has to keep his ghost identity a secret, and Jazz often gets involved in that secrecy, either by helping him keep it or by accidentally finding out. Growth is also a theme. As the story progresses, both Danny and Jazz grow as characters, both in their personal lives and in dealing with the supernatural elements around them.
One common theme is the power struggle. Ember has her own set of powers and often tries to overpower Danny, either for her own gain or just for the fun of it. So there's a constant back - and - forth in terms of who's in control.
One common theme is the exploration of their relationship. Whether it's a friendship or a budding romance, it's often at the center of the story. For example, in many fanfictions, Danny tries to protect Paulina from ghosts, which shows his care for her.
A very frequent theme is the idea of redemption. Some fanfictions explore whether Vlad can be redeemed through his relationship with Danny. It's about whether Danny's goodness can rub off on Vlad or if Vlad is too far gone. There's also the theme of family, as Vlad sees Danny as a sort of surrogate son, and this adds a whole layer of complexity to their interactions. They can be like a dysfunctional family, with all the drama and emotional turmoil that comes with it.
Another theme is the idea of overcoming obstacles. In a lot of these fanfictions, there are things like Danny's ghost - hunting duties or Sam's family issues that they have to get past before they can have that kiss. It adds drama and depth to the story. For example, in some, Danny has to balance his secret identity with his growing feelings for Sam, and this creates tension until they finally share the kiss.
One common theme is the relationship between Danny and Kitty. It often explores their dynamic, whether it's a budding romance or a complex friendship.
A common theme is the struggle between good and evil within Danny himself. Since Dark Danny is Danny's dark side personified, it's all about Danny facing his own inner demons. For example, in many fanfictions, Danny has to deal with the temptation to give in to the power that Dark Danny represents.
A frequently seen theme is the power of friendship evolving into love. They start as friends who understand each other's quirks and then it blossoms into something more. Also, the theme of sacrifice is there. In some fanfics, either Sam or Danny is willing to sacrifice something important, like Sam giving up some of her ideals or Danny risking his secret identity, for the sake of their relationship.