Chantal, tell your FYL, your husband and your boys That people do survive lung cancer. There are many on here, including my wife. She wad diagnosed with NSCLC, Stage IV, with multiple bone mets. That was two years ago! Her first chemo and radiation worked, and kept her relatively clear for almost a year. The cancer showed up again, and she is now undergoing more chemo, which seems to be working.
You all can spend a lot of time angry and grieving over what might have been or you can put that energy into hope and helping your FIL get the best treatments available to stave off the disease. He needs positive energy, not negative, to fight this disease. Make the best of each day, each week, each month, because none of us, including the doctors, know how long we have. Help you FIL have a rich and enjoyable life, whatever the length. I wish you the best. Don