Claire keeping a "squirrel baby" in cradle, explosives + Justin's alive

Jin wakes up to find himself in Claire's makeshift shack, his leg still very bloody and painful from the trap. He looks around and sees some random Dharma food, clothing and a crate of explosives from the Black Rock. He then notices a makeshift cradle and looks inside to find a hideous thing made of random animal furs, a skull and other bits. It's been dubbed "squirrel baby."

Claire comes back dragging Justin with her, who was only pretending to be dead earlier. After tying up Justin and she turns her attention to Jin saying "We'd better get that cleaned up. If there's one thing that'll kill you around here it's infection." A clever little line hinting at the infection Rousseau talked about, but referring to a literal infection.

Jin asks her if she's been by herself all this time, and she coyly says "I'm not by myself." When she steps outside, Justin tells Jin that Claire is going to kill them both.

So Claire has clearly gone off the deep end which is especially punctuated by the squirrel baby.