Another theme is the power of love. Harry's love for Sirius gives him the strength and courage to face the many obstacles in his way. It's a theme that's often explored in fanfiction as it was also a big part of the original books. In these stories, Harry's love overcomes things like the dark magic surrounding Azkaban or the threats from Voldemort's followers.
The theme of self - discovery is also present. Through the process of trying to save Sirius, Harry often discovers more about his own magical abilities and his place in the wizarding world. He might learn new spells or find out about his own hidden powers, which helps him not only in saving Sirius but also in his overall growth as a wizard.
One common theme is redemption. Sirius often feels guilty for not being there for Harry earlier, and by saving him from abuse, he is redeeming himself in a way. For example, in many stories, he reflects on how he could have prevented Harry from going to the Dursleys in the first place.
One common theme is sacrifice. Sirius is often willing to put his own life on the line to save Harry. For example, in many fics, he battles powerful dark forces without hesitation to protect the baby.
One common theme is family loyalty. Sirius is driven by his love for his brother and his sense of family duty to save Regulus. It shows that no matter how estranged they may seem, family bonds are strong.
Frequently, there's a theme of Hermione's strength in the face of abuse. Even before Sirius saves her, she might be shown as trying to resist or endure. And then after being saved, her growth and how she overcomes the trauma can be a big part of the story. The relationship between Sirius and Hermione can also explore themes of mentorship, where Sirius helps her heal and become stronger.
Another theme is family. Since Harry lacks a proper family, Sirius becomes like family to him. Fanfictions explore how they create a family - like bond in the absence of Harry's real family. It can be really emotional.
Well, in some of these fics, Sirius might time - travel to save Harry from a future threat. For example, he could see a vision of Harry being killed by Voldemort in a new and terrifying way, and then he uses time - turning magic to go back and change the course of events.
One common theme is loyalty. Sirius is extremely loyal to Harry, and vice versa. In many fanfictions, this loyalty is what gets them through tough situations, like when Harry is facing danger from Voldemort.
Adventure is also a big theme. Just like Harry had his own adventures at Hogwarts, fanfictions often have James Sirius getting into various escapades and Harry either being involved directly or guiding him from the sidelines. It gives a sense of passing on the torch of bravery.
Well, the themes often include redemption. Sirius has a complex past and in many fanfictions, he gets a chance to fully redeem himself. Also, the theme of mentorship is common. Sirius guiding Harry through the difficulties of the wizarding world. And there's the theme of friendship. Their bond that goes beyond the normal wizard - wizard relationship. In these fanfictions, they often rely on each other in tough situations which shows the depth of their friendship.
One common theme is the idea of second chances. With Harry deaged, Sirius gets a chance to be a better guardian or mentor, sort of like a redo of their relationship. For example, in many stories, Sirius is able to prevent some of the traumas Harry faced in the original story.