For the youngest's sixth birthday in July, we bought him two hermit crabs. We follow something of a mythology and ancient history theme for the naming of pets and we had just finished watching Spartacus: Blood and Sand, so we named the two crabs Crixus and Spartacus.
Crixus died sometime over the last couple days. I don't know how. His remains were found very far from his shell. His shell was in his own coconut hut but his body was, to my horror and disgust, found dismembered and partially eaten in Spartacus's hut. He may have been crawling around looking for an empty shell and Spartacus got territorial. He may have died and then was dragged to the other hut.
Spartacus seems pale and lethargic. He may be sick (a possibility if Crixus was sick) or lonely. Or maybe he just overate. It seems that crabs and other natural scavengers often cannibalize their sick/dying/dead colony mates even when other food is available. Animals are horrible sometimes.
We shouldn't have named them after gladiators. It was asking for trouble.
Update: I went to check on Spartacus. He appears to be no longer lethargic. He abandoned his old shell and has taken up residence in Crixus's old shell in. After doing some research, it seems that shell fights aren't uncommon for hermit crabs. He probably just needed the body gone (eaten or otherwise) before he was comfortable taking the shell. Horrifying and messed up, but apparently normal.