One common theme is family. Given Andromeda's break from her pure - blood family to marry Ted Tonks, a Muggle - born, family dynamics are often explored. Another theme is loyalty. Whether it's her loyalty to her new family or her struggle with the loyalty she once had to her Black family. Also, the theme of identity is prevalent. She has to define herself apart from her family's dark reputation.
One common theme is family. Since Andromeda is from the Black family, there's often exploration of her complex relationship with her family members. Another theme is love, especially the love between her and Tonks. Loss is also a frequent theme, given Tonks' fate in the original series.
Resilience is another theme. Given the difficult situations she was in, from the wizarding wars to her family issues, fanfictions often show her as a resilient character. She has to adapt to new situations and keep going.
One common theme is the idea of defying family expectations. Andromeda comes from a pure - blood family with strict traditions, and Ted is Muggle - born. Their relationship goes against what her family would want. Another theme is love conquering all. Despite the differences and the difficulties, their love prevails. For example, in many fanfictions, they face ostracism from the wizarding community, but still stay together.
One common theme is family. Andromeda comes from the Black family, and exploring how her family ties and her own choices (like marrying a Muggle - born) impact her relationship with others in the Harry Potter world, including any potential connection to Harry, is often explored.
One common theme is the internal struggle. Andromeda has to deal with her feelings for Harry while also respecting the boundaries of his own life and relationships. Another theme could be secrecy. Since it's an unusual crush, she might try to keep it a secret from others in the wizarding community.
The themes of healing and growth are quite common. Harry has been through a lot of trauma, and Andromeda, with her own experiences, can help him heal. Their relationship can be a catalyst for both of their personal growth. Also, the theme of acceptance is there. Harry is often an outsider in some ways, and Andromeda, being from a different part of the wizarding society, can offer him acceptance and understanding.
One common theme could be adventure. Writers might take Andromeda Harper on exciting quests or missions. Another theme could be friendship. They might explore the relationships she has with other characters in the story. Romance can also be a common theme, perhaps with other characters in her fictional world.
One common theme is love against all odds. Given Lupin's status as a werewolf, their relationship faces many challenges, and fanfics often explore how they overcome these obstacles to be together.
It might focus on the pregnancy itself, like the magical aspects of it in the 'Harry Potter' universe. Maybe there are special potions or spells related to pregnancy in the wizarding world that could be included. And of course, it should have some character development for Andromeda. How does this pregnancy change her as a person? How does she grow stronger or more vulnerable? This would make for an interesting and in - depth fanfic.
You can try looking on fanfiction websites like Archive of Our Own (AO3). It has a large collection of fanfics on various topics, including ones about Andromeda Tonks being pregnant. Just use the search function and type in relevant keywords.