The baby could be an alien species that Goku has never encountered before. It might have special powers related to its alien origin, like the ability to control energy in a different way than Goku and his friends.
Maybe the baby is a human with some sort of latent magical abilities. Goku, not really understanding magic at first, would have to learn how to deal with the baby's unique powers while also protecting it from those who might want to use the baby's powers for evil.
It could be a lost Saiyan baby. Since Goku is a Saiyan himself, he would feel a strong connection to the baby. This could lead to Goku teaching the baby about their Saiyan heritage and training it to become a strong warrior like him.
The plot might involve Goku finding the baby as part of some sort of mystery. For example, the baby could be a key to unlocking a hidden power or an important prophecy. Goku, being the hero he is, decides to protect the baby at all costs. He may seek help from his friends like Bulma to figure out more about the baby and its significance.
The baby could be an ordinary human baby that has some sort of latent magical ability that Raven senses. She then decides to protect the baby from the human world that may not understand or accept the baby's potential magic, and also from the magical world that might want to exploit the baby.
The baby could be an orphan from a nearby village that has been attacked. Kagome stumbles upon the baby while on her travels with Inuyasha. Since she has a big heart, she can't just leave the baby there, so she takes it with her.
The baby could be a lost elf child from a different part of the forest. Maybe their family was attacked by some dark force and Thranduil finds them by chance.
The baby could be a half - demon, related to some other important character in the series. Maybe it's the offspring of a character Sesshomaru has some history with.
The baby could be the child of a minor character from the original series who was in hiding. For example, the baby might be the offspring of a wizard who was on the run from Voldemort's followers and unfortunately didn't make it, leaving the baby behind for Harry to find.
There could be many potential authors. It might be a fan who loves the character of Dean and wanted to create a unique story around him finding a baby. It could be someone who is new to fanfiction writing and thought this would be an interesting scenario to explore.
The author could be anyone. It might be a fan who has been following the story of Zuko for a long time and thought it would be interesting to write a story where he finds a baby. It could also be someone who was inspired by other fanfictions or the original story and decided to put their own spin on it with this concept of Zuko finding a baby.
It could also be a group of fans who collaborated on the fanfiction. Each person might have contributed different ideas, like one coming up with the concept of Itachi finding the baby, another thinking about the setting, and someone else planning out how Itachi would interact with the baby in the story.
The baby might be a key to a long - forgotten mystery. It could be related to an ancient pact between the gods. Percy finding the baby could be a sign that something big is about to happen in the world of the demigods. The baby's identity could be slowly revealed as Percy and his friends investigate. It could be a symbol of hope or a harbinger of doom, depending on the circumstances surrounding its appearance.