Sakura's family members could play important roles. Her parents could initially be hesitant about her decision to adopt but later come around and become loving grandparents to the adopted child. Also, there could be other ninja in the village. For example, Hinata could be a character. She might become friends with the adopted child and help Sakura with things like cooking for the child or teaching the child some basic self - defense moves.
The plot might be that Sakura has always wanted a family but couldn't have one in the normal way. One day, she comes across a child who has been abandoned. She instantly feels a connection and decides to adopt. Along the way, they bond over shared interests. For example, if Sakura likes gardening, she teaches the child about plants and they grow a beautiful garden together, strengthening their relationship.
It could be an orphaned wizard child from a family that was killed by Death Eaters. This would give Snape an added sense of responsibility as he might feel guilty for being associated with the Death Eaters in the past.
The child could be an orphan from a small, destroyed village that Naruto comes across during one of his missions. This child might have lost their family to a powerful enemy and Naruto feels a sense of responsibility to take them in.
In this fanfiction concept, Ash's adoption could be a very heartwarming story. Maybe he meets an orphaned child during his travels. Ash, with his kind heart, decides to take the child under his wing. It could be a chance for him to pass on his knowledge of Pokemon and values like friendship and perseverance.
One idea could be that Percy discovers a demigod child who has been abandoned in the mortal world. He decides to adopt the child to protect them from monsters and to give them a proper home at Camp Half - Blood. He then has to teach the child about their demigod heritage and how to use their powers.
It's interesting because it combines two very different characters. Anko is wild and unpredictable, while Sakura is more traditional in her ninja training at first. The clash and combination of their personalities can create really engaging storylines.
In some fanfictions where Sakura adopts Naruto, it could be about Sakura seeing Naruto's need for a family. Maybe she decides to take him in after realizing how alone he has been. This can lead to a lot of character development for both of them. Naruto might start to heal from his past traumas, and Sakura could grow into a more nurturing figure.
Perhaps the child is the offspring of a Titan. This would make for an interesting story as Percy would have to deal with the potential danger and mistrust from other demigods. But Percy, being Percy, would see the good in the child and adopt them regardless. The child might have unique powers that set them apart from other demigods, like the ability to control time or space.
It could be a young wizard who lost their parents during the final battle against Voldemort. Harry feels responsible for all the orphans created by the war and decides to take this particular child under his wing.