Once the dead twins heart stops, blood stops pumping, the vessels dilate, and the conjoined twin will essentially bleed into the dead twin. If surgeons are there when the [first twin] dies, then its possible to do the surgery and save [the other].

Do conjoined twins have 2 Hearts?

They have separate hearts but share other organs. Conjoined twins are two babies who are born physically connected to each other. Conjoined twins develop when an early embryo only partially separates to form two individuals.

Are Brittany and Abby Hensel separated?

Brittany and Abby are separated at the waist. They have two arms and legs, three lungs, two hearts, and two stomachs. Because they have two brains, each twin controls one side of the body, and can only feel sensations on their respective side.