I don't have enough information to say exactly who Tara Reade is in these stories. She could be an ordinary person with an interesting story, or she might be a public figure in a specific community.
Beatrix Potter's books, such as 'The Tale of Peter Rabbit', are also similar. Potter's stories are centered around small animals in a bucolic setting. Her detailed illustrations and simple yet engaging stories about the animals' escapades bear some resemblance to the Thornton Burgess Animal Stories.
The main character is Thornton, of course. He's the center of the fanfiction and all the stories revolve around his adventures, his Pokemon training, and his interactions with other characters in the Pokemon world.
Since I don't have the actual details of Jazz Thornton's story when she was 3 years old, we can only make some general assumptions. Maybe she was just beginning to form memories, playing with simple toys, and interacting with her family in a very innocent and carefree way. It could also be that she showed early signs of her personality traits that would later shape her into the person she is today, but this is all speculation without more knowledge of her specific story.
One common theme is the struggle between good and evil. Since Tara is often portrayed as a good character in the Buffyverse and vampires are typically associated with evil, the fanfictions often explore how Tara deals with the vampire elements, whether it's fighting them or trying to understand them.
A book like 'Watership Down' by Richard Adams is also in the same vein. It follows a group of rabbits on their journey to find a new home. It delves deep into the social structure, instincts, and personalities of the animals, similar to how Thornton Burgess portrays his animal characters.