Joined at the heart, it's painful to realize that these Israeli twins were doomed from start. Ha'aretz reports that the ultra-Orthodox parents would have used modern diagnostics (cf. my previous post). Furthermore: "A source close to the family said that had the diagnosis of the conjoined twins been presented in time, the parents would have sought rabbinical approval to stop the pregnancy."
It's not the first time that an Orthodox family had Siamese twins who shared a heart.
Philadelphia, 1977. The country's top halakhic authority, R. Moses Feinstein, agreed orally to let C. Everett Koop terminate one (non-viable) of the doomed twins so that the other (viable) twin could live. Here's the story as told by Rabbi Moshe Tendler. R. Feinstein apparently treats the non-viable twin as a rodef, a pursuer, who may be terminated (cp. fetus that threatens a mother's life). I believe that R. Bleich (Tradition 31:1, 1996) and R. Tendler also suggest another rationale, based on classifying the non-viable twin as a treifa, a person who cannot live for long. R. Shabtai Rappoport harmonizes the two approaches. From any standpoint, R. Feinstein's decision is highly controversial because it seems to permit the active termination of a newborn for the sake of another's life.
R. Moshe Feinstein's compassionate and sui generis decision has been used to critique the Catholic position in a similar, more famous Siamese twins case in England. (by Leora Rosen, Gregg Easterbrook)
Sobering case to consider, as we enter the gates of repentence, the gates of judgment, as The Supreme Judge decides who shall live and who shall die.
May you be written and sealed in the book of life, a redemptive Rosh ha-Shanah (Jewish New Year) to all,
Another link: essay on conjoined twins cases