In this fanfiction, Sakura might turn into a baby due to a scientific experiment gone wrong. Her family and friends are shocked at first. They have to adjust to taking care of a baby. Meanwhile, the scientists who caused the accident are trying to find a way to reverse it. Sakura, as a baby, has a completely different perception of the world and her actions as a baby start to have unforeseen effects on those around her.
Tomoyo would also be an important character. She would be very worried about Sakura. She might use her skills in making costumes to create some special baby clothes for Sakura. And she would be constantly by Sakura's side, taking care of her and trying to comfort her.
In a 'sakura turned into a baby fanfic', it could start with Sakura getting too close to a mysterious portal. The portal's energy zaps her and she is transformed into a baby. Her closest companion might notice some strange behavior before the full transformation. Once she's a baby, they need to protect her from those who might take advantage of her vulnerable state. They also have to deal with the challenges of taking care of a baby, like feeding, changing diapers, all while desperately looking for a solution to return her to normal.
Sakura herself would obviously be a main character, just in her baby form. Her best friend could also be a main character. For example, if she has a friend like Tomoyo, Tomoyo would likely be very involved. She would be trying to figure out how to help Sakura and also taking care of her, making sure she has cute clothes even as a baby.
Maybe there was a magical mishap. A powerful wizard was trying to cast a spell on another dimension but it backfired and hit Supergirl instead, turning her into a baby. In the fanfiction, Kara's friends like Lois Lane could try to take care of her in a more human way since she has lost all her powers as a baby. They would have to keep her identity a secret too.
One possibility could be that a powerful spell was cast on the superheroine by a villain. Maybe the villain wanted to weaken her and thought turning her into a baby would be the best way. In the fanfiction, the superheroine's friends would then have to figure out how to reverse the spell while also protecting the now - helpless baby version of her.
The baby in such a fanfiction could look really unique. With Gaara's red hair and Sakura's pink hair, the child might have a very interesting hair color, perhaps a blend of the two. And in terms of abilities, it could have some new and unexpected powers that combine the sand - based techniques and Sakura's chakra - enhanced strength.
She would be both curious and empathetic. Curious about how the baby ended up where she found it and empathetic towards the baby's situation. So she would start to form an emotional bond with the baby right away. She might talk to the baby softly, trying to soothe it, and then start making plans on how to best care for it in the long run.
One common theme could be the contrast between Sakura's original personality and her new bimbo - like behavior. It might explore how her relationships with other characters change as a result of this transformation.
There could be her family members. Her parents might play a role in either supporting or not believing her new - found ability. And her siblings could be either jealous or in awe of her. Also, there could be a wise old man or woman in the village who has some knowledge about seeing the future and can guide her.