To write a mother - daughter fanfic, start with a strong opening that shows the dynamic between them right away. Maybe it's an argument or a heart - to - heart conversation. Then, build the story around a central conflict. It could be external, like dealing with a difficult neighbor, or internal, such as the daughter's insecurities. As you write, use dialogue to bring their relationship to life. Let them express their feelings and thoughts through what they say to each other.
When writing a mother - daughter fanfic, consider different settings. It could be in a small town where everyone knows each other, or in a big city. The setting can influence their relationship. Also, think about their backstories. Maybe the mother had a difficult childhood that affects how she parents the daughter. You can also include other characters to add more depth to the story, like the daughter's best friend or the mother's sister. All these elements combined will make a great mother - daughter fanfic.