Bioethics discussion - marriage of conjoined twins

I’m interested on the Catholic bioethic take on this question:

Suppose there were a set of conjoined twins who had separate heads and/or upper bodies but who shared a lower body, legs, sexual organs, etc. The twins both wish to get married and have children.

What issues or concerns might arise in such a situation and what would be the correct Catholic response to said issues?

For example, can two people who share a body marry two different spouses and would conjugal relations be licit? Talk me through this…

I’m thinking they’d be required to remain celibate. As do those with any other sexual disorders (like those with same sex attraction). It would be a terribly heavy cross to carry, but I’m pretty sure that’s what the church would say.

Chang and Eng Bunker, the original Siamese twins, were married & had children. I’m not sure, but I think others have married, too. So it’s not a hypothetical question. However, they weren’t Catholic.

Ok, so Sue and Sarah are conjoined, wouldn’t both need to consent?
Also, if both did consent and only shared waist down parts, wouldn’t that be like an incestuous threesome? Maybe I’m thinking way too into this, but it just doesn’t seem right. At. All.

you could always contact the National Catholic Bioethics Center

If I were ever in the position of needing to advise someone on this issue, I would. But for now it’s just a thought experiment.

I know in marriage you exchange rights to your body with your spouse, hence the expression “marital debt.” I don’t know how this works when the body is also shared by someone else. I agree that both would need to consent, because otherwise it would be rape of one of the twins, right?

I think Chang and Eng Bunker were attached at the abdomen and had separate lower bodies. Maybe this changes the morality of the marital act? I guess you’d still have to deal with the fact that the twin would always be present for the other twin’s marital relations…

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