A frequently seen theme is the idea of redemption. As Smaug was a rather evil dragon, the fanfictions often explore if the dragon child can break free from that negative legacy. There's also the theme of discovery. The dragon child discovers new places, new friends or foes, and new aspects of itself. For instance, it might discover a love for beauty in a world it was taught to only see as something to conquer. This discovery can lead to a change in its character and goals.
Often, there are themes related to the protection of the unborn. Since Smaug is a powerful and feared creature, the idea of something precious (the unborn) within him could lead to themes of safeguarding. Also, there might be themes of change, as Smaug's state would surely bring about some sort of transformation in his behavior or the way others perceive him.
Power is also a major theme. Since they are the child of a dragon, they usually possess great and sometimes uncontrollable power. The story may revolve around how they learn to master it. Another theme is discovery. They discover their heritage, new magical places, and secrets about the dragon world as the story progresses.
One interesting Smaug dragon child fanfiction is 'The Legacy of Smaug's Heir'. It explores the journey of a young dragon, offspring of Smaug, as it tries to find its place in a world that fears dragons. The story is full of adventure as the dragon child discovers hidden powers and makes unexpected alliances.
One common theme is the idea of family. The dragon and the human child form a unique family unit, often defying the norms of both their species. Another theme is acceptance. The dragon has to accept the human child as part of its life, and the child has to accept living with a dragon, which is a very different kind of existence.
Well, perhaps there could be a plot where Smaug is the last of his kind and in order to preserve the dragon species, some unforeseen magic makes him pregnant. He then has to go through the process of gestation which is completely new to him. Along the way, he might learn about new forms of power and weakness, and his view of the world around him, including other races like dwarves and elves, could change as he experiences this unique state.
I'm not entirely sure if there is a specific male pregnant dragon Smaug fanfiction out there. It's a rather unusual concept. It depends on how creative the fanfiction community has been with the character of Smaug. You might want to start by using search terms like 'Smaug male pregnancy fanfiction' in search engines dedicated to fan works. There may be some hidden gems if you're persistent in your search.
One common theme is friendship. Since they are such important characters in the Naruto series, fanfictions often explore how they could have been closer friends as children. Another theme is rivalry, showing how their competitive nature started at a young age.
Many 'child Draco' fanfictions deal with the theme of self - discovery. He's in a world full of magic and complex social hierarchies. Fanfic writers often explore how he figures out his place in this world. Additionally, the theme of his relationship with authority figures, such as his parents and teachers at Hogwarts, is also common. These relationships shape his character and are often central to the stories.
One common theme is friendship. Fanfictions often explore Harry's relationships with Ron and Hermione during their childhood years. Another theme is discovery of magic. Since Harry's a child, his first experiences with magic are often elaborated on.
One common theme is legacy. The child is often seen as carrying on Ash's dreams and achievements in the Pokémon world.