Hello, and welcome.
It sounds like you're doing a great job with your very young kittens and they're coming along nicely! : )
I'm sorry this one kitten has developed this discharge.
The pus you mention, could be the symptom of a vaginal infection or could indicate a urinary tract infection, just to mention a few possibilities; it could also be a yeast infection.
She should definitely be evaluated by the vet, so you can get a definite diagnosis and she can be treated. The discharge would need to be tested and/or cultured, to know what kind of bacteria is present, so the vet knows what kind of antibiotic to prescribe, if necessary.
Try your best to have her seen by the vet, tomorrow and please let me know how she's doing and what the vet's findings are. Thanks!
I hope all will be well with your furry little girl!
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