What do children with cancer and dark jokes have in common? They never get old!
Why are you joking about people who are suffering from cancer?
I just think that laughing about cancer is the best way to relieve anxiety about it.
I understand wanting to lighten the mood by joking about something. But you should consider how a parent that was lost a child to cancer might feel if they heard that joke. It may be best to keep your jokes to lighter topics.