There is also the theme of overcoming challenges. Percy as a single father has to face various difficulties, such as financial problems if his partner was the main earner before, or dealing with the child's emotional problems due to the absence of one parent. These fanfictions often show how he overcomes these challenges with determination and love for his child.
One common theme is the struggle to balance the demigod world and normal parenting. Percy has to protect his child from mythological threats while also ensuring they have a normal childhood like going to school, making friends. Another theme is the passing on of values. Since Percy has his own set of values from his own adventures, he tries to pass those on to his child. And there's often the theme of loneliness too. Being a single father in a world where most people don't understand the demigod situation can be isolating.
One common theme is the struggle of balancing ninja duties and fatherhood. Naruto has to be out there protecting the village but also be there for his child.
One common theme is the struggle of single parenting. Naruto has to handle all the responsibilities of raising a child alone, like providing for them, protecting them, and teaching them right from wrong. Another theme is the clash of different worlds. Since it's a crossover, there are elements from different anime universes that Naruto has to deal with while raising his child.
One common theme is redemption. Draco, as a former Death Eater, often has to atone for his past while being a single father. Another theme is family. It focuses on how Draco builds a new family with Hermione. And love, of course, as the relationship between Draco and Hermione develops.
One common theme is sacrifice. Tony often has to sacrifice his time as Iron Man to be there for his child. For example, in many fics, he misses important Avengers meetings because his child is sick or has a school event.
One common theme is sacrifice. James has to sacrifice his own desires and time to focus on raising Harry alone. Another theme is love. His love for Harry is unconditional and drives him to do whatever it takes to protect and raise him well.
One common theme is redemption. Draco is often shown trying to atone for his past actions by being a good father. Another theme is the struggle against prejudice. People in the wizarding world may still have a negative view of him, but he has to rise above it for his child.
One common theme is sacrifice. Harry often has to sacrifice his own desires or time for his child. For instance, he might give up on a dangerous but exciting adventure to be there for his kid's first day at Hogwarts.
One common theme is sacrifice. Percy often has to sacrifice his own time and freedom to take care of the child. Another theme is protection. He has to protect the child from the various threats in the demigod world. And there's also the theme of growth, both for Percy as he matures into a father figure and for the child as they grow up under Percy's care.
The theme of self - discovery is often present. Adrian, as a single father, discovers parts of himself he didn't know existed. He might find that he has a natural talent for cooking healthy meals for his child, or that he can be really patient during bedtime tantrums. Also, the theme of family support or lack thereof can be explored. Some fanfictions show how his family either steps up to help or is too preoccupied with other things to be of much assistance.