You can try some popular fanfic websites like Archive of Our Own (AO3). It has a large collection of various fanfics, and you might be able to find some Stefan x daughter ones there.
Well, a great Stefan x daughter fanfic might focus on the emotional bond between them. For example, when the daughter is going through a tough time at school and Stefan is there to support and guide her. He could share his own life experiences to help her cope.
One common theme is the clash of different worlds. Harry comes from a world of magic and wizards, while Stefan is from a world of vampires. So, there's often exploration of how these two very different worlds collide and interact.
One great 'harry x stefan fanfic' is 'The Unlikely Bond'. It explores how Harry and Stefan, coming from different fictional universes, form a unique friendship. Their shared sense of loyalty and struggle against dark forces is really well - depicted in it.
There is also 'The Unlikely Bond'. In this fanfiction, it starts with Caroline and Stefan being forced to work together on a school project. Their initial dislike for each other gradually turns into a deep connection as they discover more about themselves through the process.
Stefan Salvatore x OC fanfiction often explores unique relationships. In such stories, the OC (Original Character) can bring new dynamics to the 'The Vampire Diaries' universe. It allows fans to create their own storylines that might not be possible with just the canon characters. For example, the OC could be a witch who has a special connection with Stefan, leading to all kinds of adventures and romances.
Writing about family relationships in a positive light, such as a father teaching his daughter valuable life lessons or a daughter helping her father overcome a difficult time. These are all great themes that are far from the inappropriate 'daughter x father' idea.
Archive of Our Own (AO3) is a great place. It has a large collection of fanfictions, and you can easily search for 'Caroline x Stefan' ones. There are different categories and tags to help you narrow down your search.
The popularity of Damon x Stefan fanfiction stems from the fact that Damon and Stefan are two very interesting characters. Their personalities are quite different, yet they are bound by their brotherly bond. In fanfiction, writers can play around with this dynamic. They can create scenarios where the two have to rely on each other more than ever, or explore the idea of a forbidden love between them. Also, fans love to see different interpretations of their relationship, whether it's a more friendly or a more passionate one.