One common theme is mentorship. Celestia is often Twilight's mentor, so the fanfics explore how Celestia imparts knowledge and wisdom to Twilight. Another theme is friendship. Despite their different positions, they form a deep friendship which is often depicted. And power is also a theme, like how Twilight grows in power with Celestia's guidance.
One common theme is possessiveness. Since Celestia is a yandere, she will be extremely possessive of Twilight. Another theme could be the power imbalance. Celestia has more power and authority, and this can create a complex situation when combined with her yandere nature. Love in an extreme form is also a theme. It's not a normal, healthy love but rather an obsessive one that can drive the plot.
Often, you'll find themes like legacy. Since Celestia has such a long and important history in Equestria, Twilight has to deal with the expectations that come with being her daughter. Also, friendship still plays a role as Twilight's friends react to this new situation, adding a layer of complexity to their relationships.
A common theme is mentorship. Celestia often serves as a mentor to Twilight, guiding her in magic and leadership. Another theme is friendship. They develop a deep bond through various adventures.
One common theme is self - discovery. Twilight has to come to terms with being Celestia's daughter, which changes her perception of herself. Another theme is family, exploring the bond between Twilight and Celestia that goes beyond just a student - teacher relationship. Also, power and responsibility are often themes, as Twilight may inherit certain powers or responsibilities from Celestia.
One common theme is mentorship. Celestia is often portrayed as Twilight's mentor, guiding her in her studies and growth as a unicorn. Another theme is friendship. Since friendship is a big part of MLP, their relationship in fanfics is often centered around strengthening their bond as friends.
One common theme is identity. Twilight has to come to terms with being Celestia's daughter and what that means for her as an individual. For example, she may question her own self - worth and abilities in a different light.
Sometimes, there could be a theme related to the challenges she faces during the pregnancy. This could include physical challenges, like dealing with the discomfort, or more complex challenges like how her role in the story's world is affected by her being pregnant. There may also be themes of protection, with other characters in the fic trying to ensure her and the unborn child's safety.
One common theme is the idea of redemption. Discord has a past of causing chaos, and in many fanfics, his relationship with Celestia is part of his journey towards redemption. For example, Celestia may offer him a chance to prove himself and do good for Equestria.
One common theme is mentorship. Since Celestia was Twilight's mentor, many fanfictions explore this relationship further, like Twilight facing a difficult magical problem and Celestia guiding her through it.
Well, identity crisis is often seen. Twilight has to re - evaluate who she is once she learns about her relation to Celestia. Also, the theme of mentorship gets a new twist. Instead of just being a mentor - student relationship, it becomes a mother - daughter relationship which can be explored in terms of how Celestia's teachings change. And there's also the theme of acceptance among the pony community as they come to terms with this new relationship.