Käsemädchen had a bad habit of having her familiar, a ferret, bite anyone who pissed her off, including other party members. One night in a tavern in Sigil, Havok’s githzerai fighter/thief had suffered this indignity for the last time and chopped the ferret in half.
In Second Edition, the penalties for losing a familiar were much greater than in Third: first, Kasey had to make a system shock check (essentially a Constitution check) or die; after succeeding at this check, she still lost a point of Constitution, which lowered her hit points. Echo, seeing her chance to get rid of the other female mage in the party (yes, she was jealous), took advantage of Kasey’s weakened state (and Marc’s dumbfounded one) to start slinging spells. Several other members of the party jumped in, looking to take out the annoying and generally despised character. (Kasey’s personality was annoying but the character was hated because it was dumped into the game from a previous “Monty Haul” campaign, and had spells, items and levels that completely outclassed the rest of the party.) Marc, seeing his beloved über-character down to around one hit point (Kasey hadn’t seen single-digit hit points in years) quickly used the final wish on her Ring of Three Wishes to wish that Käsemädchen hadn’t ordered the ferret to bite Havok’s character. That was the last time anyone suffered a ferret bite.