Married Siblings

So, I watched the latest episode of Private Practice yesterday and I was a little intrigued by one of the storylines.

For those of you who don't know, Private Practice is a spin-off of Grey's Anatomy. It follows Dr. Addison Montgomery (Kate Walsh) as she left Seattle Grace to join her best friend's private practice. The practice has a slew of different types of doctors, such as Dr. Cooper Freeman (Paul Adelstein) who is a pediatrician; Dr. Violet Turner (Amy Brennemen) a psychiatrist; Dr. Pete Wilder (Tim Daly) who specializes in different types of medicine. And they are all under the watchful eyes of Dr. Naomi Bennett (Audra McDonald) and Dr. Sam Bennett (Taye Diggs), a divorced couple who started the practice.

Anyway, back to the storyline at hand. In this particular episode a young couple wanted to have a child. They had been married five years and were having trouble getting pregnant. Apparently, they were both very shy in junior high until they found each other - and had been together ever since.

Dr. Montgomery and Dr. Naomi Bennett took the case and looked into reasonings behind why they were unable to get pregnant. After further investigation, it became not why they couldn't get pregnant - but why they shouldn't. Apparently, the happy couple just so happened to be brother and sister.

Not the typical type, however. These two were only related because each of their parents were unable to conceive so they looked for the help of a sperm donor - and both sets picked the exact same one.

Obviously, this is a lot to take - especially when you have devoted your life and are absolutely head over heels in love with this person.

The doctors of the practice were obviously on both sides of the fence on this one. In order to continue to be married, the wife opted to have her tubes tied, so she and her 'husband' could stay together, but wouldn't risk getting pregnant.

At the end of the episode, the 'husband' confessed that he had actually figured out they were brother and sister before they had gotten married - this led to the 'wife' getting completely grossed out because he had known before everything went as far as it did and didn't tell her.

Anyway, my question is simple. This could actually happen if people aren't careful - I mean it's a simple mistake that neither child knew they had been created due to sperm donation. What are your thoughts on the subject? Is it disgusting to continue to want to be married to the love of your life, after just finding out that you are actually related? What would you do? If you found out the love of your life was actually your brother/sister could you stay with them?

Very odd topic I know, but it truly got me thinking about what people would be able to do. It's a very rough situation to be in.