One possible reason could be mind control. Maybe an enemy of the village found a way to manipulate Kushina's mind and make her turn against her own baby. Another reason might be a misunderstanding. For example, she could have been tricked into believing that Naruto was a threat to the village in some way.
In fanfiction, the idea of Naruto attacking Kushina is very uncharacteristic as they are mother - son. It could be a very dark or alternate universe scenario. Maybe in a plot where Naruto is mind - controlled or in a completely warped reality where family bonds are reversed.
Naruto would likely be deeply hurt, not just physically but also emotionally. He has always idolized his mother, so an attack from her would be a huge blow to his psyche. His trust in family and those close to him could be severely damaged.
Maybe the village elders would get involved. They might try to figure out what went wrong with Kushina and at the same time, find a way to protect Naruto. Naruto could grow up with a lot of suspicion and fear from the villagers because of this incident, which would shape his character in a different way than in the original story.
Perhaps there's a time - travel element involved. Naruto from the future, who has been through some horrible experiences, travels back in time and, in a state of confusion or rage, attacks Kushina. Or it could be that a powerful villain has the ability to manipulate Naruto's emotions and uses that power to make him turn on his mother. This would create a very complex and dark plotline that challenges the normal Naruto narrative.
In some fanfictions, it might be due to an alternate timeline or reality. A change in the past could lead to Kushina having different beliefs or loyalties. It could also be related to a new power or curse that affects her judgment and causes her to see Naruto as an enemy. However, this is often a very dark and dramatic turn in fanfiction stories.
Kushina would take care of baby Naruto very tenderly. She would make sure he is well - fed before sleep, perhaps by breastfeeding him or giving him a warm bottle. She'd also check his diaper and change it if needed.
Well, a fanfiction could explore how Minato and Kushina's love for each other is reflected in their care for Naruto. Their strong bond as a couple helps them create a loving and stable environment for their baby.
In fanfiction, Kushina might also interact with baby Naruto in a protective way when facing potential danger. Imagine a situation where some rogue ninjas are after Naruto for some reason. Kushina would put herself in front of Naruto without hesitation, using her chakra chains to fend off the attackers. And after the danger has passed, she would comfort Naruto, telling him that he is safe now and that she will always protect him.
One possible development for Naruto is that he begins to show signs of leadership. Even as a baby, he might gather the other village kids around him and lead them in some small play - adventures. For Kushina, she could develop a more nurturing side. She might start to think more about the well - being of the whole village because she realizes that Naruto will grow up in this environment. So, she could be involved in activities that improve the living conditions in the village, all because of her love for Naruto.