What Happens When One Conjoined Twin Dies? Consider this a trigger warning, as the story below discusses the death of a newborn baby and the processes taken to separate a living conjoined twin from a deceased conjoined twin. Article continues below advertisementBelow, we explore what science says about what happens when one conjoined twin is stillborn and the other conjoined twin is born alive. Article continues below advertisementWhat happens when one conjoined twin dies? With only approximately 12 sets of conjoined twins living globally today, per the Ranker report, this underscores the rarity of one or both twins surviving.