My Family Had 2 Children with CF

Tré LaRosa avatar

by Tré LaRosa |

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(Courtesy of Tré LaRosa)

It was unlikely that my parents would bear two children with CF. When both parents carry a CF mutation but don’t have the disease itself, there is a 1 in 4 chance that a child will have CF. To determine the likelihood of two events independent of one another to both happen (since one child having CF doesn’t affect if any succeeding children will have CF), you multiply the probabilities of both. Some quick math (1/4 times 1/4) gets us to a 1 in 16 chance of both kids having CF — a 6.25 percent chance.

Aside from CF, my sister has been the most prominent feature of my writing. I’ve written about her death, my guilt from her dying days, a letter she wrote before her death, and so much more. One topic I haven’t explored as much is how two siblings with CF grow up under the same roof. When two people with CF are in close proximity, there is a serious risk of cross-contamination, so what happens when those two people with CF are siblings?

First, I want to be very clear: My sister and I were always careful about our health. We avoided drinking from the same cup and never shared utensils or anything that could directly transmit bacteria. That isn’t to say we never hugged or spent time together. Whenever one of us was sick, we would avoid each other around the house, but if one of us was sick during car rides to visit family or while on vacation, there wasn’t really much we could do. My parents have been married my entire life, so it wasn’t like there was a legitimate option for us to divide time between different houses.

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Our family’s guiding mantra has always been along the lines of: “Be careful, conscious, and intentional about how we live and take care of ourselves, but absolutely do not sacrifice our humanity for a hypothetical risk.” In other words, we were cautious and aware of risks, but we were siblings. Removing the humanity of our relationship by constantly viewing each other as a risk was not what my parents wanted us to believe.

This idea brings up another point. How much could we actually do to prevent cross-contamination? And in our case, what exactly even is cross-contamination? Alyssa and I likely were exposed to similar contaminants on a daily basis. If my sister cultured a bug that I didn’t for a year, but I ended up culturing it sometime later, it would be difficult to pinpoint if I cultured it due to “cross-contamination” (sharing the same air as my sister) or exposure to the contaminant in an environment she’d also occupied (some public place).

Once Alyssa got a double-lung transplant, it got a little trickier. Since people who’ve had transplants are no longer as likely to culture bacteria in their lungs, they can share spaces with people who have CF and present less risk. I didn’t worry much about my sister reculturing the bacteria I have (she still had them in her sinuses anyway). I worried far more about transient viruses. I worried that I was on the cusp of a cold or flu if I had even a slightly scratchy throat or sore joints. My sister was more at risk of catching viruses. Avoiding each other in these cases was reasonable and doable, mostly because I wasn’t living at home at the time and the viruses would go away after a couple of days.

From whichever perspective you view it — mine, my sister’s, my parents’ — it’s difficult to frame minimizing the risks inherent in CF siblings sharing the same space without dehumanizing us. It wouldn’t have been a healthy upbringing for us to avoid each other, to not live as siblings in a world where not many others understand our plight.

My sister and I did not want to view each other as risks. We shared a bond that was unlike any other in our world. It wouldn’t have been right to eliminate the one relationship that made us feel like somebody understood us. Losing that will never stop haunting me.

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Note: Cystic Fibrosis News Today is strictly a news and information website about the disease. It does not provide medical advice, diagnosis, or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website. The opinions expressed in this column are not those of Cystic Fibrosis News Today, or its parent company, BioNews Services, and are intended to spark discussion about issues pertaining to cystic fibrosis.


Lia avatar


Thank you again for your articles! Always helpful for a CF parent.

Luisa Palazola avatar

Luisa Palazola

So glad you find our content helpful, and Tré is an awesome columnist!

Bonnie Wright avatar

Bonnie Wright

We also have 2 sons with CF. Their ages are 49 and 47. They have both had double lung transplants and the 47 year old has also had a single lung transplant when the first transplant rejected. We bless every day that we have them and they are remarkable individuals. Both are married and have incredible and supportive wives who have become the breadwinners for their respective marriages.

Luisa Palazola avatar

Luisa Palazola

Hi Bonnie! Incredible to hear (or read!) Here's to them continuing to do well :)
- Luisa, Community Manager at CF News Today


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