He can't be killed and doesn't age... So he's not a kid at all, then. Not being able to die, he could get into all sorts of things and still survive... though he's sure it has consequences, it sounds convenient.

"Guess we have some things in common," he says, resting the edge of his knife against his fingers and inspecting the blade for any trace of the blood that was on it. After Czeslaw spilled his secrets, he supposes he doesn't have much issue telling a few of his own.