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Markkula Center for Applied Ethics


Mary Francis Garcia ’23


Mary Francis Garcia is majoring in neuroscience with a minor in biotechnology and is a 2021-22 health care ethics intern at the Markkula Center for Applied Ethics. Views are her own.

To start, I ask that you entertain the following scenario:

Congratulations! After a long 9 months, you have given birth to your first child; a baby girl! But she entered this world significantly underweight and with noticeable physiological abnormalities. Concerned, you come to learn that she has Fanconi Anemia (FA), a hereditary lifelong and life-threatening disease primarily characterized as gradual bone marrow failure. Effects include physical abnormalities, organ defects, and an increased risk of certain cancers (in the bone marrow, neck, skin, gastrointestinal tract, or genital tract). The only solution: a bone marrow transplant. Unfortunately, both you and your partner are not a human leukocyte antigen (HLA) match for your daughter and therefore cannot donate your own. Without a HLA match, bone marrow transplants would be attacked by your daughter's immune system, resulting in treatment failure. Other families would then turn to a sibling, but this is your first child and she has no siblings. What to do then? Surely you would provide her with a sibling whose umbilical cord stem cells could be transferred. This sibling would be her savior, hence the term, savior sibling. 

Now this scenario is far from made-up. This was a real journey that Lisa and Jack Nash underwent through the late 1990s after the birth of their daughter with FA, Molly, on July 4, 1994. They were able to create a savior sibling via in vitro fertilization (IVF). The process of IVF entails collecting eggs from the mother, fertilizing them in a petri dish, screening them for genetic abnormalities, and then implanting a chosen embryo into the mother to be carried to term. For this to work for the Nashs, the implanted embryo would need to fulfill two requirements: 1.) not be a carrier of FA and 2.) be an HLA match to Molly. Naturally conceiving was a possibility, but offered lower chances of successfully producing a child with the above requirements–only 18.8% in fact. Furthermore, the chances of giving birth to another child with FA was 25% and FA alone was reason enough for others to abort. Lisa and Jack thought this irresponsible, so IVF was the way to go. Ideally, the resulting child would be a perfect match whose umbilical stem cells would keep Molly alive.

After six years characterized by 4 failed IVF attempts with one miscarriage and one miscarriage scare (all while Molly’s health, and platelet counts, were declining), Lisa and Jack’s efforts had shown fruitful. On August 29, 2000, they gave birth to a baby boy, Adam. The blood from his umbilical cord was collected and shortly transferred to Molly. Years later, Molly’s platelet counts were healthy and her bone marrow was functioning normally. As the cherry on top, Adam and Molly acted as normal siblings and loved each other very much.

The case of Molly was miraculous and the Nashs had their happy ending. Nonetheless, their success forces us to consider the implications of savior siblings, which includes introducing a slippery slope argument against it. One widely discussed facet of the slippery slope argument is described by the book and movie My Sister’s Keeper by Jodi Picoult. In a plot that was inspired by Molly’s journey, it tells the story of Anna, a child born to keep her older sister, Kate, alive. In her short lifetime, Anna had undergone multiple blood transfusions and painful bone marrow transplants, all for the health of Kate. Having had enough at thirteen, Anna enlists legal help to sue her parents for medical emancipation so she ultimately does not have to donate a kidney to her sister. 

Although this story is fiction, it materializes a genuine fear about how far savior siblings can go, that is, using more than a sibling's umbilical cord stem cells. The slippery slope argument has also touched on the realm that considers creating a savior for family members that are not necessarily siblings or for individuals that are not at all related.

When thinking about savior siblings, there are many moral and bioethical considerations to be taken into account as the Nash's actions did not go without ridicule. The couple mainly received backlash from religious groups that claim moral status to the many embryos the Nashs created. In reality, the embryos that were not used were preserved, but that was after the couple had implanted another one to have a third child, a girl. Nonetheless, religious groups were not satisfied with the fact that the Nashs had brought so many of those embryos into the world to choose only a select few.

The main bioethical consideration for the case of savior siblings is the Kantian perspective of using another human as a means to an end. The Kantian perspective is explicitly opposed to this. Savior siblings may imply a certain commodification of the savior as a person to be used when the first child is in need of something of theirs. The question then gets asked: to what degree did the parents give birth to this child because they wanted another child? Or did they do it because they wanted to save the first one? With this in mind, we can examine how the principles of autonomy and justice are violated. The sibling did not (and could not) consent to being the savior of their brother/sister before being born. Furthermore, in bringing to light our slippery slope argument, a young savior is too young to make medical decisions for themselves and are at the hands of their parents. Not only could this lead to the detrimental physical side effects of associated procedures, but harmful mental effects could soon follow, such as the feeling of owing. Whether it is the donor to the recipient or vice versa, there may be a feeling of “someone owes someone something” or “one person is in debt to the other.”

As we have seen in the amazing story of Molly and the Nashs, a savior sibling has been shown to be life-saving in the best of circumstances. But it is also important to acknowledge the potential harm it could cause. Thus, more research still has yet to be done to explore the weight and validity of the moral and ethical arguments regarding the creation of savior siblings. Nonetheless, the pursuit of savior siblings should be done with caution and with the best intent for both the savior and the sibling.


Jun 23, 2022

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