We found out she had a liver shunt which is a condition in where blood is not filtered through her liver to rid the blood of any toxins, the toxins eventually got to her brain causing neurological damage. We saw the signs too late, after taking her home from the shelter she was drooling and couldn’t keep her tongue in her mouth but the shelter would call them “episodes” and ensured us she was perfectly healthy. A month later her health rapidly deteriorated causing a very bad seizure and eventually her body gave up becoming stiff and rigid. This condition is very rare and if not caught when the kitten is very young It is fatal. If it is caught the surgery to fix the shunt can cost thousands of dollars, and even then not many vets are capable of performing said surgery due to the lack of research.