In a timeline of events in the lives of the original "Siamese" twins...
"7 Aug 1870 While playing checkers with the President of Liberia during a transatlantic voyage, Chang is suddenly striken with paralysis along the right side of his body.
17 Jan 1874 Chang dies of a blood clot in the brain; Eng dies two and a half hours later, perhaps from fright."
That must be a strange experience: sitting next to your dead Siamese twin. Okay, so having a Siamese twin in the first place isn't exactly normal, but you'd be used to it since things would have been that way for literally your entire life. But while being attached to another person is different, being attached to a DEAD person is an entirely different matter. And it's not just any dead person, it's your Siamese twin. I think the queerness of this whole thing stems from myriad factors...
-A family member has just died. That seems to bother people by itself.
-You're even closer to this family member than normal. It's your identical twin.
-Your twin is attached to you (as he always has been). But now he's dead. This is unusual behavior for him.
-There's like over a hundred pounds of dead person ATTACHED TO YOUR BODY.
-This mass of dead flesh that is connected to your own looks just like you.
-What looks like a dead version of you is not just right next to you, it's ATTACHED to you.
-Where does alive you end and dead twin begin?
-You cannot move further away from this dead body because it is fused to you.
-You must lie down because you have an amount of dead weight equivalent to your own connected to your body.
-This means your are TRAPPED on the floor (or wherever) with a dead body.
-There are probably people around you chatting it up about how your twin is dead or freaking out over this. I doubt that's going to help you.
-The mass of tissues fused to your body is still warm, but soon it will be both cold and DECAYING.
-In all probability, your life is measured in hours. So on top of everything else, you realize that you are DYING.
-There is absolutely no hope that this is going to become less freaky in the future. It's kind of hard to calm down in a situation where the corpse you are attached to is only getting more dead over time (as all corpses do).