The entity texture pathnames for baby bands (e.g., entity/panda/lazy_panda_baby.png) are different from the adult pandas (entity/panda/panda_lazy.png), which is the naming pattern used for all other entities: <entity>_<variant>[_baby].png.
Admittedly not the most important thing in the world, but easy to fix, and no reason a new name should add inconsistencies that may create problems for shell scripts, etc., that people (me, for example) write to process these things.
Thank you for your report!
After consideration, the issue is being closed as Won't Fix.
Please note that this is not the same as Working as Intended, as this bug report correctly describes behavior in the game that might not be the intended or desirable behavior, but it will not be fixed right now. Sometimes, this is because the issue reported is minor and/or impossible to change without large architectural changes to the code base.
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