We have several people at WhatNext who are battling lung cancer. I am sure someone will reach out to you soon. In the meantime, I wanted to suggest that you check out WhatNext member Dulcinea. Just enter her name in the box on the "People" page. She is fighting 3A lung cancer, too.
Additionally, when you are on the People page, on the left hand side you will see that you can search for people with a specific cancer. Expand the drop box and click on lung cancer. You can view their journeys and if/when you are ready, you can either follow them or reach out to them.
Hope this helps. Please let me know if there is anything else I can do. I'm keeping your sister-in-law in my thoughts.