In a fanfiction, the baby tigress could befriend a mysterious creature from outside the Valley of Peace. This creature has unique powers that could enhance her kung fu skills. However, the other residents of the valley are suspicious of this new friendship. The baby tigress has to balance her loyalty to her new friend and her duty to the valley, all while trying to master new kung fu abilities that her friendship brings.
One idea could be a story where the baby tigress discovers a new, secret martial arts technique in the Valley of Peace. Maybe she stumbles upon an ancient scroll that was forgotten. She then has to practice in secret because she's not sure if it's a good or bad technique. As she hones her skills, she starts to show off new moves during sparring sessions with the Furious Five, leaving them all very curious.
A fanfiction could focus on the baby tigress's early days at the Jade Palace. She might struggle to fit in with the other students. So, she decides to prove herself by taking on a task that seems impossible for a young cub, like guarding a special relic all by herself for a night. During this time, she overcomes her fears and insecurities, and in the end, earns the respect of her peers and masters.