We have been looking back into our family history as well. My husband's side had a lot of cancers, but nothing with CF. There isn't even anyone with asthma! My side on the other hand there is tons of stuff. We have had lots of Crohn's disease, infant deaths, congenital heart disease, cancer and the list goes on and on. I have a feeling that within all that something correlates with CF. My grandmother's sister died in infancy and they has no idea what it was. 10 million americans are carriers, which I think is an astronomical number! So I can not see how all those carriers could have a family history.
Hope everyone is well!