Hey everyone! I'm a closest KFP fan trying to make my debut and strike up conversation with other fans and share my ideas, including head canons!
Anyway, a few peeps in the KFP fandom have made note that Southern Chinese tigers, Tigress’ species, are larger than pandas, and while obviously the films don't need to portray each animal 100% accurately I personally head canon that Tigress might have been born prematurely/sickly. The runt, so to speak, which is why she is smaller than Po even as an adult.
Her parents might have given her up thinking she wouldn’t survive or hoping that the people at the orphanage would be able to care for her better than they could.
I'm sorry if there is already a thread like this, but I'm open to hear other people's thoughts!